161574209 has 2 divisors, whose sum is σ = 161574210. Its totient is φ = 161574208.

The previous prime is 161574187. The next prime is 161574211. The reversal of 161574209 is 902475161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 154132225 + 7441984 = 12415^2 + 2728^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161574209 is a prime.

It is a super-2 number, since 2×161574209² = 52212450027951362, which contains 22 as substring.

Together with 161574211, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (161574709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80787104 + 80787105.

It is an arithmetic number, because the mean of its divisors is an integer number (80787105).

Almost surely, 2^161574209 is an apocalyptic number.

It is an amenable number.

161574209 is a deficient number, since it is larger than the sum of its proper divisors (1).

161574209 is an equidigital number, since it uses as much as digits as its factorization.

161574209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 161574209 is about 12711.1844058687. The cubic root of 161574209 is about 544.6581578209.

The spelling of 161574209 in words is "one hundred sixty-one million, five hundred seventy-four thousand, two hundred nine".