161500397 has 2 divisors, whose sum is σ = 161500398. Its totient is φ = 161500396.

The previous prime is 161500387. The next prime is 161500453. The reversal of 161500397 is 793005161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 111218116 + 50282281 = 10546^2 + 7091^2 .

It is a cyclic number.

It is not a de Polignac number, because 161500397 - 2¹⁴ = 161484013 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 (161500307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80750198 + 80750199.

It is an arithmetic number, because the mean of its divisors is an integer number (80750199).

Almost surely, 2^161500397 is an apocalyptic number.

It is an amenable number.

161500397 is a deficient number, since it is larger than the sum of its proper divisors (1).

161500397 is an equidigital number, since it uses as much as digits as its factorization.

161500397 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5670, while the sum is 32.

The square root of 161500397 is about 12708.2806468853. The cubic root of 161500397 is about 544.5752063985.

The spelling of 161500397 in words is "one hundred sixty-one million, five hundred thousand, three hundred ninety-seven".