25642436634 has 24 divisors (see below), whose sum is σ = 56050286292. Its totient is φ = 8471836800.

The previous prime is 25642436629. The next prime is 25642436639. The reversal of 25642436634 is 43663424652.

25642436634 is a `hidden beast` number, since 2 + 5 + 6 + 4 + 2 + 4 + 3 + 6 + 634 = 666.

It is an interprime number because it is at equal distance from previous prime (25642436629) and next prime (25642436639).

It can be written as a sum of positive squares in 2 ways, for example, as 25329677409 + 312759225 = 159153^2 + 17685^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 25642436634.

It is not an unprimeable number, because it can be changed into a prime (25642436639) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6301417 + ... + 6305484.

Almost surely, 2^25642436634 is an apocalyptic number.

25642436634 is an abundant number, since it is smaller than the sum of its proper divisors (30407849658).

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

25642436634 is a wasteful number, since it uses less digits than its factorization.

25642436634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12607022 (or 12607019 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 45.

The spelling of 25642436634 in words is "twenty-five billion, six hundred forty-two million, four hundred thirty-six thousand, six hundred thirty-four".