640025634 has 8 divisors (see below), whose sum is σ = 1280051280. Its totient is φ = 213341876.

The previous prime is 640025629. The next prime is 640025641. The reversal of 640025634 is 436520046.

It is a sphenic number, since it is the product of 3 distinct primes.

640025634 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53335464 + ... + 53335475.

It is an arithmetic number, because the mean of its divisors is an integer number (160006410).

Almost surely, 2^640025634 is an apocalyptic number.

640025634 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

640025634 is a wasteful number, since it uses less digits than its factorization.

640025634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106670944.

The product of its (nonzero) digits is 17280, while the sum is 30.

The square root of 640025634 is about 25298.7279126837. The cubic root of 640025634 is about 861.7853814381.

The spelling of 640025634 in words is "six hundred forty million, twenty-five thousand, six hundred thirty-four".