25521623431 has 2 divisors, whose sum is σ = 25521623432. Its totient is φ = 25521623430.

The previous prime is 25521623341. The next prime is 25521623447. The reversal of 25521623431 is 13432612552.

Together with previous prime (25521623341) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25521623431 is a prime.

It is a super-2 number, since 2×25521623431² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25521623131) 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 as a sum of consecutive naturals, namely, 12760811715 + 12760811716.

It is an arithmetic number, because the mean of its divisors is an integer number (12760811716).

Almost surely, 2^25521623431 is an apocalyptic number.

25521623431 is a deficient number, since it is larger than the sum of its proper divisors (1).

25521623431 is an equidigital number, since it uses as much as digits as its factorization.

25521623431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43200, while the sum is 34.

The spelling of 25521623431 in words is "twenty-five billion, five hundred twenty-one million, six hundred twenty-three thousand, four hundred thirty-one".