164243621 has 8 divisors (see below), whose sum is σ = 171671424. Its totient is φ = 156839760.

The previous prime is 164243591. The next prime is 164243623. The reversal of 164243621 is 126342461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 164243621 - 2²² = 160049317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164243623) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8855 + ... + 20171.

It is an arithmetic number, because the mean of its divisors is an integer number (21458928).

Almost surely, 2^164243621 is an apocalyptic number.

It is an amenable number.

164243621 is a deficient number, since it is larger than the sum of its proper divisors (7427803).

164243621 is a wasteful number, since it uses less digits than its factorization.

164243621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11971.

The product of its digits is 6912, while the sum is 29.

The square root of 164243621 is about 12815.7567470673. The cubic root of 164243621 is about 547.6412718296.

It can be divided in two parts, 164243 and 621, that multiplied together give a triangular number (101994903 = T₁₄₂₈₂).

The spelling of 164243621 in words is "one hundred sixty-four million, two hundred forty-three thousand, six hundred twenty-one".