64400836 has 12 divisors (see below), whose sum is σ = 112814380. Its totient is φ = 32168160.

The previous prime is 64400821. The next prime is 64400837. The reversal of 64400836 is 63800446.

It can be written as a sum of positive squares in 2 ways, for example, as 40449600 + 23951236 = 6360^2 + 4894^2 .

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 64400798 and 64400807.

It is not an unprimeable number, because it can be changed into a prime (64400837) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3255 + ... + 11806.

Almost surely, 2^64400836 is an apocalyptic number.

It is an amenable number.

64400836 is a deficient number, since it is larger than the sum of its proper divisors (48413544).

64400836 is a wasteful number, since it uses less digits than its factorization.

64400836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16134 (or 16132 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 31.

The square root of 64400836 is about 8025.0131464067. The cubic root of 64400836 is about 400.8333376652.

The spelling of 64400836 in words is "sixty-four million, four hundred thousand, eight hundred thirty-six".