164388021 has 16 divisors (see below), whose sum is σ = 250675200. Its totient is φ = 93868848.

The previous prime is 164388013. The next prime is 164388041. The reversal of 164388021 is 120883461.

It is not a de Polignac number, because 164388021 - 2³ = 164388013 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164388041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55660 + ... + 58538.

It is an arithmetic number, because the mean of its divisors is an integer number (15667200).

Almost surely, 2^164388021 is an apocalyptic number.

It is an amenable number.

164388021 is a deficient number, since it is larger than the sum of its proper divisors (86287179).

164388021 is a wasteful number, since it uses less digits than its factorization.

164388021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5608.

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 164388021 is about 12821.3891993029. The cubic root of 164388021 is about 547.8017168957.

The spelling of 164388021 in words is "one hundred sixty-four million, three hundred eighty-eight thousand, twenty-one".