640370637 has 32 divisors (see below), whose sum is σ = 1011830400. Its totient is φ = 398870784.

The previous prime is 640370609. The next prime is 640370639. The reversal of 640370637 is 736073046.

640370637 is a `hidden beast` number, since 640 + 3 + 7 + 0 + 6 + 3 + 7 = 666.

It is not a de Polignac number, because 640370637 - 2¹⁵ = 640337869 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640370639) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 58783 + ... + 68819.

It is an arithmetic number, because the mean of its divisors is an integer number (31619700).

Almost surely, 2^640370637 is an apocalyptic number.

It is an amenable number.

640370637 is a deficient number, since it is larger than the sum of its proper divisors (371459763).

640370637 is a wasteful number, since it uses less digits than its factorization.

640370637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10202 (or 10196 counting only the distinct ones).

The product of its (nonzero) digits is 63504, while the sum is 36.

The square root of 640370637 is about 25305.5455779953. The cubic root of 640370637 is about 861.9402008283.

The spelling of 640370637 in words is "six hundred forty million, three hundred seventy thousand, six hundred thirty-seven".