1261407744 has 120 divisors (see below), whose sum is σ = 3654565200. Its totient is φ = 418848768.

The previous prime is 1261407713. The next prime is 1261407781. The reversal of 1261407744 is 4477041621.

It is a happy number.

It is a super-2 number, since 2×1261407744² = 3182298993246339072, which contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 1261407699 and 1261407708.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2105557 + ... + 2106155.

It is an arithmetic number, because the mean of its divisors is an integer number (30454710).

Almost surely, 2^1261407744 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1261407744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1827282600).

1261407744 is an abundant number, since it is smaller than the sum of its proper divisors (2393157456).

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

1261407744 is an equidigital number, since it uses as much as digits as its factorization.

1261407744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1080 (or 1061 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

The square root of 1261407744 is about 35516.3025102558. The cubic root of 1261407744 is about 1080.4843917660.

The spelling of 1261407744 in words is "one billion, two hundred sixty-one million, four hundred seven thousand, seven hundred forty-four".