640250776 has 32 divisors (see below), whose sum is σ = 1315414080. Its totient is φ = 289732000.

The previous prime is 640250761. The next prime is 640250783. The reversal of 640250776 is 677052046.

It is a congruent number.

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, 3951 + ... + 36001.

It is an arithmetic number, because the mean of its divisors is an integer number (41106690).

Almost surely, 2^640250776 is an apocalyptic number.

It is an amenable number.

640250776 is an abundant number, since it is smaller than the sum of its proper divisors (675163304).

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

640250776 is a wasteful number, since it uses less digits than its factorization.

640250776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32295 (or 32291 counting only the distinct ones).

The product of its (nonzero) digits is 70560, while the sum is 37.

The square root of 640250776 is about 25303.1771918074. The cubic root of 640250776 is about 861.8864197548.

The spelling of 640250776 in words is "six hundred forty million, two hundred fifty thousand, seven hundred seventy-six".