164133621 has 14 divisors (see below), whose sum is σ = 246088950. Its totient is φ = 109421928.

The previous prime is 164133601. The next prime is 164133637. The reversal of 164133621 is 126331461.

164133621 is a `hidden beast` number, since 1 + 6 + 4 + 1 + 33 + 621 = 666.

It can be written as a sum of positive squares in only one way, i.e., 143065521 + 21068100 = 11961^2 + 4590^2 .

It is not a de Polignac number, because 164133621 - 2¹⁰ = 164132597 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 (164133601) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 111846 + ... + 113303.

Almost surely, 2^164133621 is an apocalyptic number.

It is an amenable number.

164133621 is a deficient number, since it is larger than the sum of its proper divisors (81955329).

164133621 is an frugal number, since it uses more digits than its factorization.

164133621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225167 (or 225152 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 164133621 is about 12811.4644361993. The cubic root of 164133621 is about 547.5189860183.

The spelling of 164133621 in words is "one hundred sixty-four million, one hundred thirty-three thousand, six hundred twenty-one".