164188621 has 2 divisors, whose sum is σ = 164188622. Its totient is φ = 164188620.

The previous prime is 164188589. The next prime is 164188667. The reversal of 164188621 is 126881461.

164188621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 103815721 + 60372900 = 10189^2 + 7770^2 .

It is a cyclic number.

It is not a de Polignac number, because 164188621 - 2⁵ = 164188589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (164188021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82094310 + 82094311.

It is an arithmetic number, because the mean of its divisors is an integer number (82094311).

Almost surely, 2^164188621 is an apocalyptic number.

It is an amenable number.

164188621 is a deficient number, since it is larger than the sum of its proper divisors (1).

164188621 is an equidigital number, since it uses as much as digits as its factorization.

164188621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18432, while the sum is 37.

The square root of 164188621 is about 12813.6107713634. The cubic root of 164188621 is about 547.5801357512.

The spelling of 164188621 in words is "one hundred sixty-four million, one hundred eighty-eight thousand, six hundred twenty-one".