161908801 has 2 divisors, whose sum is σ = 161908802. Its totient is φ = 161908800.

The previous prime is 161908787. The next prime is 161908819. The reversal of 161908801 is 108809161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 150185025 + 11723776 = 12255^2 + 3424^2 .

It is a cyclic number.

It is not a de Polignac number, because 161908801 - 2⁷ = 161908673 is a prime.

It is not a weakly prime, because it can be changed into another prime (161908001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80954400 + 80954401.

It is an arithmetic number, because the mean of its divisors is an integer number (80954401).

Almost surely, 2^161908801 is an apocalyptic number.

It is an amenable number.

161908801 is a deficient number, since it is larger than the sum of its proper divisors (1).

161908801 is an equidigital number, since it uses as much as digits as its factorization.

161908801 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 34.

The square root of 161908801 is about 12724.3389219244. The cubic root of 161908801 is about 545.0338626099.

The spelling of 161908801 in words is "one hundred sixty-one million, nine hundred eight thousand, eight hundred one".