1261586016 has 144 divisors (see below), whose sum is σ = 3916785600. Its totient is φ = 398348928.

The previous prime is 1261585993. The next prime is 1261586021. The reversal of 1261586016 is 6106851621.

1261586016 is a `hidden beast` number, since 1 + 2 + 61 + 586 + 0 + 16 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 143475 + ... + 152013.

It is an arithmetic number, because the mean of its divisors is an integer number (27199900).

Almost surely, 2^1261586016 is an apocalyptic number.

1261586016 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 1261586016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1958392800).

1261586016 is an abundant number, since it is smaller than the sum of its proper divisors (2655199584).

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

1261586016 is an equidigital number, since it uses as much as digits as its factorization.

1261586016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8583 (or 8563 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 1261586016 is about 35518.8121423000. The cubic root of 1261586016 is about 1080.5352902010.

The spelling of 1261586016 in words is "one billion, two hundred sixty-one million, five hundred eighty-six thousand, sixteen".