1256231113551 has 96 divisors (see below), whose sum is σ = 1940847480000. Its totient is φ = 780759834624.

The previous prime is 1256231113549. The next prime is 1256231113567. The reversal of 1256231113551 is 1553111326521.

1256231113551 is a `hidden beast` number, since 1 + 2 + 5 + 62 + 31 + 1 + 13 + 551 = 666.

It is not a de Polignac number, because 1256231113551 - 2¹ = 1256231113549 is a prime.

It is a super-2 number, since 2×1256231113551² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1256231113751) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1771834785 + ... + 1771835493.

It is an arithmetic number, because the mean of its divisors is an integer number (20217161250).

Almost surely, 2^{1256231113551} is an apocalyptic number.

1256231113551 is a deficient number, since it is larger than the sum of its proper divisors (684616366449).

1256231113551 is a wasteful number, since it uses less digits than its factorization.

1256231113551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1433 (or 1430 counting only the distinct ones).

The product of its digits is 27000, while the sum is 36.

The spelling of 1256231113551 in words is "one trillion, two hundred fifty-six billion, two hundred thirty-one million, one hundred thirteen thousand, five hundred fifty-one".