3640620816 has 150 divisors (see below), whose sum is σ = 12257555310. Its totient is φ = 1040159232.

The previous prime is 3640620791. The next prime is 3640620829. The reversal of 3640620816 is 6180260463.

3640620816 is a `hidden beast` number, since 3 + 640 + 6 + 2 + 0 + 8 + 1 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 2173424400 + 1467196416 = 46620^2 + 38304^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 34840 + ... + 92168.

Almost surely, 2^3640620816 is an apocalyptic number.

3640620816 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3640620816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6128777655).

3640620816 is an abundant number, since it is smaller than the sum of its proper divisors (8616934494).

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

3640620816 is a wasteful number, since it uses less digits than its factorization.

3640620816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57363 (or 57341 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 3640620816 is about 60337.5572591400. The cubic root of 3640620816 is about 1538.3617840931.

The spelling of 3640620816 in words is "three billion, six hundred forty million, six hundred twenty thousand, eight hundred sixteen".