64399566 has 32 divisors (see below), whose sum is σ = 160581888. Its totient is φ = 16727040.

The previous prime is 64399549. The next prime is 64399571. The reversal of 64399566 is 66599346.

It is a happy number.

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, 69235 + ... + 70158.

It is an arithmetic number, because the mean of its divisors is an integer number (5018184).

Almost surely, 2^64399566 is an apocalyptic number.

64399566 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

64399566 is an abundant number, since it is smaller than the sum of its proper divisors (96182322).

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

64399566 is a wasteful number, since it uses less digits than its factorization.

64399566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139416.

The product of its digits is 1049760, while the sum is 48.

The square root of 64399566 is about 8024.9340184203. The cubic root of 64399566 is about 400.8307028045.

The spelling of 64399566 in words is "sixty-four million, three hundred ninety-nine thousand, five hundred sixty-six".