64720836 has 48 divisors (see below), whose sum is σ = 177670080. Its totient is φ = 20304000.

The previous prime is 64720823. The next prime is 64720841. The reversal of 64720836 is 63802746.

64720836 is a `hidden beast` number, since 647 + 2 + 0 + 8 + 3 + 6 = 666.

It is a super-2 number, since 2×64720836² = 8377573225077792, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 64720836.

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, 15790 + ... + 19461.

It is an arithmetic number, because the mean of its divisors is an integer number (3701460).

Almost surely, 2^64720836 is an apocalyptic number.

It is an amenable number.

64720836 is an abundant number, since it is smaller than the sum of its proper divisors (112949244).

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

64720836 is a wasteful number, since it uses less digits than its factorization.

64720836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35281 (or 35273 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 64720836 is about 8044.9261028303. The cubic root of 64720836 is about 401.4961386127.

It can be divided in two parts, 64720 and 836, that added together give a palindrome (65556).

The spelling of 64720836 in words is "sixty-four million, seven hundred twenty thousand, eight hundred thirty-six".