164243591 has 2 divisors, whose sum is σ = 164243592. Its totient is φ = 164243590.

The previous prime is 164243587. The next prime is 164243623. The reversal of 164243591 is 195342461.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 164243591 - 2² = 164243587 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (164246591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82121795 + 82121796.

It is an arithmetic number, because the mean of its divisors is an integer number (82121796).

Almost surely, 2^164243591 is an apocalyptic number.

164243591 is a deficient number, since it is larger than the sum of its proper divisors (1).

164243591 is an equidigital number, since it uses as much as digits as its factorization.

164243591 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25920, while the sum is 35.

The square root of 164243591 is about 12815.7555766330. The cubic root of 164243591 is about 547.6412384864.

The spelling of 164243591 in words is "one hundred sixty-four million, two hundred forty-three thousand, five hundred ninety-one".