64139392 has 16 divisors (see below), whose sum is σ = 127777950. Its totient is φ = 32069632.

The previous prime is 64139371. The next prime is 64139393. The reversal of 64139392 is 29393146.

It can be written as a sum of positive squares in only one way, i.e., 63107136 + 1032256 = 7944^2 + 1016^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a super-2 number, since 2×64139392² = 8227723212259328, which contains 22 as substring.

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (64139393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 250417 + ... + 250672.

Almost surely, 2^64139392 is an apocalyptic number.

It is an amenable number.

64139392 is a deficient number, since it is larger than the sum of its proper divisors (63638558).

64139392 is an equidigital number, since it uses as much as digits as its factorization.

64139392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 501103 (or 501091 counting only the distinct ones).

The product of its digits is 34992, while the sum is 37.

The square root of 64139392 is about 8008.7072614749. The cubic root of 64139392 is about 400.2901894243.

The spelling of 64139392 in words is "sixty-four million, one hundred thirty-nine thousand, three hundred ninety-two".