163405566 has 32 divisors (see below), whose sum is σ = 365998080. Its totient is φ = 54037368.

The previous prime is 163405549. The next prime is 163405589. The reversal of 163405566 is 665504361.

163405566 is a `hidden beast` number, since 1 + 63 + 40 + 556 + 6 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 163405566.

It is a congruent number.

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, 5056 + ... + 18771.

It is an arithmetic number, because the mean of its divisors is an integer number (11437440).

Almost surely, 2^163405566 is an apocalyptic number.

163405566 is an abundant number, since it is smaller than the sum of its proper divisors (202592514).

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

163405566 is a wasteful number, since it uses less digits than its factorization.

163405566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23965 (or 23959 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The square root of 163405566 is about 12783.0186575785. The cubic root of 163405566 is about 546.7082344127.

The spelling of 163405566 in words is "one hundred sixty-three million, four hundred five thousand, five hundred sixty-six".