156163221 has 24 divisors (see below), whose sum is σ = 234858624. Its totient is φ = 103692960.

The previous prime is 156163211. The next prime is 156163243. The reversal of 156163221 is 122361651.

156163221 is a `hidden beast` number, since 1 + 5 + 6 + 1 + 632 + 21 = 666.

It is not a de Polignac number, because 156163221 - 2¹⁵ = 156130453 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (156163211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 67140 + ... + 69426.

It is an arithmetic number, because the mean of its divisors is an integer number (9785776).

Almost surely, 2^156163221 is an apocalyptic number.

It is an amenable number.

156163221 is a deficient number, since it is larger than the sum of its proper divisors (78695403).

156163221 is an equidigital number, since it uses as much as digits as its factorization.

156163221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2583 (or 2571 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 156163221 is about 12496.5283579080. The cubic root of 156163221 is about 538.5089422092.

The spelling of 156163221 in words is "one hundred fifty-six million, one hundred sixty-three thousand, two hundred twenty-one".