1256611261590 has 48 divisors (see below), whose sum is σ = 3267255420000. Its totient is φ = 335089552896.

The previous prime is 1256611261579. The next prime is 1256611261597. The reversal of 1256611261590 is 951621166521.

1256611261590 is a `hidden beast` number, since 1 + 2 + 5 + 6 + 611 + 26 + 1 + 5 + 9 + 0 = 666.

It is a super-2 number, since 2×1256611261590² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1256611261597) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5632486 + ... + 5851334.

It is an arithmetic number, because the mean of its divisors is an integer number (68067821250).

Almost surely, 2^{1256611261590} is an apocalyptic number.

1256611261590 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1256611261590 is an abundant number, since it is smaller than the sum of its proper divisors (2010644158410).

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

1256611261590 is a wasteful number, since it uses less digits than its factorization.

1256611261590 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282661 (or 282658 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 45.

The spelling of 1256611261590 in words is "one trillion, two hundred fifty-six billion, six hundred eleven million, two hundred sixty-one thousand, five hundred ninety".