161566049 has 2 divisors, whose sum is σ = 161566050. Its totient is φ = 161566048.

The previous prime is 161566039. The next prime is 161566051. The reversal of 161566049 is 940665161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 95257600 + 66308449 = 9760^2 + 8143^2 .

It is a cyclic number.

It is not a de Polignac number, because 161566049 - 2⁸ = 161565793 is a prime.

It is a super-2 number, since 2×161566049² = 52207176378940802, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 161566051, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (161566019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80783024 + 80783025.

It is an arithmetic number, because the mean of its divisors is an integer number (80783025).

Almost surely, 2^161566049 is an apocalyptic number.

It is an amenable number.

161566049 is a deficient number, since it is larger than the sum of its proper divisors (1).

161566049 is an equidigital number, since it uses as much as digits as its factorization.

161566049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 161566049 is about 12710.8634246459. The cubic root of 161566049 is about 544.6489886897.

The spelling of 161566049 in words is "one hundred sixty-one million, five hundred sixty-six thousand, forty-nine".