25643634 has 16 divisors (see below), whose sum is σ = 52942080. Its totient is φ = 8272080.

The previous prime is 25643621. The next prime is 25643663. The reversal of 25643634 is 43634652.

It is a junction number, because it is equal to n+sod(n) for n = 25643595 and 25643604.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68749 + ... + 69120.

It is an arithmetic number, because the mean of its divisors is an integer number (3308880).

Almost surely, 2^25643634 is an apocalyptic number.

25643634 is an abundant number, since it is smaller than the sum of its proper divisors (27298446).

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

25643634 is a wasteful number, since it uses less digits than its factorization.

25643634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137905.

The product of its digits is 51840, while the sum is 33.

The square root of 25643634 is about 5063.9543836808. The cubic root of 25643634 is about 294.8898717528.

The spelling of 25643634 in words is "twenty-five million, six hundred forty-three thousand, six hundred thirty-four".