161252591 has 2 divisors, whose sum is σ = 161252592. Its totient is φ = 161252590.

The previous prime is 161252587. The next prime is 161252617. The reversal of 161252591 is 195252161.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161252591 - 2² = 161252587 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 (161252521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80626295 + 80626296.

It is an arithmetic number, because the mean of its divisors is an integer number (80626296).

Almost surely, 2^161252591 is an apocalyptic number.

161252591 is a deficient number, since it is larger than the sum of its proper divisors (1).

161252591 is an equidigital number, since it uses as much as digits as its factorization.

161252591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5400, while the sum is 32.

The square root of 161252591 is about 12698.5271193158. The cubic root of 161252591 is about 544.2965319868.

The spelling of 161252591 in words is "one hundred sixty-one million, two hundred fifty-two thousand, five hundred ninety-one".