165237491 has 2 divisors, whose sum is σ = 165237492. Its totient is φ = 165237490.

The previous prime is 165237487. The next prime is 165237511. The reversal of 165237491 is 194732561.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 165237491 - 2² = 165237487 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (165230491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82618745 + 82618746.

It is an arithmetic number, because the mean of its divisors is an integer number (82618746).

Almost surely, 2^165237491 is an apocalyptic number.

165237491 is a deficient number, since it is larger than the sum of its proper divisors (1).

165237491 is an equidigital number, since it uses as much as digits as its factorization.

165237491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45360, while the sum is 38.

The square root of 165237491 is about 12854.4735792641. The cubic root of 165237491 is about 548.7436790281.

The spelling of 165237491 in words is "one hundred sixty-five million, two hundred thirty-seven thousand, four hundred ninety-one".