640279100 has 36 divisors (see below), whose sum is σ = 1462536600. Its totient is φ = 242631360.

The previous prime is 640279099. The next prime is 640279141. The reversal of 640279100 is 1972046.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 166595 + ... + 170394.

Almost surely, 2^640279100 is an apocalyptic number.

It is an amenable number.

640279100 is an abundant number, since it is smaller than the sum of its proper divisors (822257500).

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

640279100 is a wasteful number, since it uses less digits than its factorization.

640279100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 337022 (or 337015 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 640279100 is about 25303.7368781767. The cubic root of 640279100 is about 861.8991292076.

The spelling of 640279100 in words is "six hundred forty million, two hundred seventy-nine thousand, one hundred".