163664640 has 108 divisors (see below), whose sum is σ = 566302464. Its totient is φ = 43640832.

The previous prime is 163664639. The next prime is 163664659. The reversal of 163664640 is 46466361.

163664640 is a `hidden beast` number, since 1 + 6 + 3 + 6 + 6 + 4 + 640 = 666.

It is a super-2 number, since 2×163664640² = 53572228772659200, which contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 163664595 and 163664604.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4417 + ... + 18623.

Almost surely, 2^163664640 is an apocalyptic number.

163664640 is a gapful number since it is divisible by the number (10) 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 163664640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (283151232).

163664640 is an abundant number, since it is smaller than the sum of its proper divisors (402637824).

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

163664640 is a wasteful number, since it uses less digits than its factorization.

163664640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14234 (or 14217 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The square root of 163664640 is about 12793.1481661083. The cubic root of 163664640 is about 546.9970109916.

The spelling of 163664640 in words is "one hundred sixty-three million, six hundred sixty-four thousand, six hundred forty".