25642139431 has 4 divisors (see below), whose sum is σ = 27150500592. Its totient is φ = 24133778272.

The previous prime is 25642139429. The next prime is 25642139461. The reversal of 25642139431 is 13493124652.

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

It is not a de Polignac number, because 25642139431 - 2¹ = 25642139429 is a prime.

It is a super-2 number, since 2×25642139431² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25642139461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 754180555 + ... + 754180588.

It is an arithmetic number, because the mean of its divisors is an integer number (6787625148).

Almost surely, 2^25642139431 is an apocalyptic number.

25642139431 is a deficient number, since it is larger than the sum of its proper divisors (1508361161).

25642139431 is a wasteful number, since it uses less digits than its factorization.

25642139431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1508361160.

The product of its digits is 155520, while the sum is 40.

The spelling of 25642139431 in words is "twenty-five billion, six hundred forty-two million, one hundred thirty-nine thousand, four hundred thirty-one".