640925958 has 32 divisors (see below), whose sum is σ = 1339027200. Its totient is φ = 204132896.

The previous prime is 640925939. The next prime is 640925969. The reversal of 640925958 is 859529046.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 167713 + ... + 171491.

It is an arithmetic number, because the mean of its divisors is an integer number (41844600).

Almost surely, 2^640925958 is an apocalyptic number.

640925958 is an abundant number, since it is smaller than the sum of its proper divisors (698101242).

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

640925958 is a wasteful number, since it uses less digits than its factorization.

640925958 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5036.

The product of its (nonzero) digits is 777600, while the sum is 48.

The square root of 640925958 is about 25316.5155185306. The cubic root of 640925958 is about 862.1892832464.

The spelling of 640925958 in words is "six hundred forty million, nine hundred twenty-five thousand, nine hundred fifty-eight".