64640620 has 36 divisors (see below), whose sum is σ = 149213232. Its totient is φ = 23504800.

The previous prime is 64640593. The next prime is 64640621. The reversal of 64640620 is 2604646.

It is not an unprimeable number, because it can be changed into a prime (64640621) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10936 + ... + 15775.

It is an arithmetic number, because the mean of its divisors is an integer number (4144812).

Almost surely, 2^64640620 is an apocalyptic number.

It is an amenable number.

64640620 is an abundant number, since it is smaller than the sum of its proper divisors (84572612).

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

64640620 is a wasteful number, since it uses less digits than its factorization.

64640620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26742 (or 26729 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 64640620 is about 8039.9390544954. The cubic root of 64640620 is about 401.3301965394.

The spelling of 64640620 in words is "sixty-four million, six hundred forty thousand, six hundred twenty".