161856599 has 2 divisors, whose sum is σ = 161856600. Its totient is φ = 161856598.

The previous prime is 161856593. The next prime is 161856631. The reversal of 161856599 is 995658161.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161856599 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 (161856593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80928299 + 80928300.

It is an arithmetic number, because the mean of its divisors is an integer number (80928300).

Almost surely, 2^161856599 is an apocalyptic number.

161856599 is a deficient number, since it is larger than the sum of its proper divisors (1).

161856599 is an equidigital number, since it uses as much as digits as its factorization.

161856599 is an evil number, because the sum of its binary digits is even.

The product of its digits is 583200, while the sum is 50.

The square root of 161856599 is about 12722.2874908564. The cubic root of 161856599 is about 544.9752804208.

The spelling of 161856599 in words is "one hundred sixty-one million, eight hundred fifty-six thousand, five hundred ninety-nine".