25640406 has 24 divisors (see below), whose sum is σ = 60605064. Its totient is φ = 7769760.

The previous prime is 25640401. The next prime is 25640429. The reversal of 25640406 is 60404652.

It is a happy number.

25640406 is a `hidden beast` number, since 256 + 4 + 0 + 406 = 666.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 25640406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25640401) 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, 64551 + ... + 64946.

It is an arithmetic number, because the mean of its divisors is an integer number (2525211).

Almost surely, 2^25640406 is an apocalyptic number.

25640406 is an abundant number, since it is smaller than the sum of its proper divisors (34964658).

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

25640406 is a wasteful number, since it uses less digits than its factorization.

25640406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129516 (or 129513 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 25640406 is about 5063.6356503998. The cubic root of 25640406 is about 294.8774977337.

The spelling of 25640406 in words is "twenty-five million, six hundred forty thousand, four hundred six".