64139218 has 32 divisors (see below), whose sum is σ = 113783040. Its totient is φ = 26891280.

The previous prime is 64139209. The next prime is 64139219. The reversal of 64139218 is 81293146.

It is a super-2 number, since 2×64139218² = 8227678571303048, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (64139219) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47671 + ... + 48997.

It is an arithmetic number, because the mean of its divisors is an integer number (3555720).

Almost surely, 2^64139218 is an apocalyptic number.

64139218 is a deficient number, since it is larger than the sum of its proper divisors (49643822).

64139218 is a wasteful number, since it uses less digits than its factorization.

64139218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1379 (or 1353 counting only the distinct ones).

The product of its digits is 10368, while the sum is 34.

The square root of 64139218 is about 8008.6963982910. The cubic root of 64139218 is about 400.2898274494.

The spelling of 64139218 in words is "sixty-four million, one hundred thirty-nine thousand, two hundred eighteen".