1261231776 has 288 divisors, whose sum is σ = 4421813760. Its totient is φ = 348727680.

The previous prime is 1261231747. The next prime is 1261231801. The reversal of 1261231776 is 6771321621.

It is a happy number.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

1261231776 is a `hidden beast` number, since 1 + 2 + 612 + 31 + 7 + 7 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×1261231776² = 3181411185584228352, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

Its product of digits (21168) is a multiple of the sum of its prime factors (126).

It is a self number, because there is not a number n which added to its sum of digits gives 1261231776.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 40684881 + ... + 40684911.

It is an arithmetic number, because the mean of its divisors is an integer number (15353520).

Almost surely, 2^1261231776 is an apocalyptic number.

1261231776 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1261231776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2210906880).

1261231776 is an abundant number, since it is smaller than the sum of its proper divisors (3160581984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1261231776 is an frugal number, since it uses more digits than its factorization.

1261231776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126 (or 43 counting only the distinct ones).

The product of its digits is 21168, while the sum is 36.

The square root of 1261231776 is about 35513.8251389512. The cubic root of 1261231776 is about 1080.4341464428.

The spelling of 1261231776 in words is "one billion, two hundred sixty-one million, two hundred thirty-one thousand, seven hundred seventy-six".