256400432131 has 4 divisors (see below), whose sum is σ = 256410562752. Its totient is φ = 256390301512.

The previous prime is 256400432129. The next prime is 256400432221. The reversal of 256400432131 is 131234004652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 256400432131 - 2¹ = 256400432129 is a prime.

It is a super-2 number, since 2×256400432131² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 256400432093 and 256400432102.

It is not an unprimeable number, because it can be changed into a prime (256400432231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5027251 + ... + 5077996.

It is an arithmetic number, because the mean of its divisors is an integer number (64102640688).

Almost surely, 2^256400432131 is an apocalyptic number.

256400432131 is a deficient number, since it is larger than the sum of its proper divisors (10130621).

256400432131 is a wasteful number, since it uses less digits than its factorization.

256400432131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10130620.

The product of its (nonzero) digits is 17280, while the sum is 31.

Adding to 256400432131 its reverse (131234004652), we get a palindrome (387634436783).

The spelling of 256400432131 in words is "two hundred fifty-six billion, four hundred million, four hundred thirty-two thousand, one hundred thirty-one".