161566051 has 2 divisors, whose sum is σ = 161566052. Its totient is φ = 161566050.

The previous prime is 161566049. The next prime is 161566073. The reversal of 161566051 is 150665161.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161566051 - 2¹ = 161566049 is a prime.

It is a super-2 number, since 2×161566051² = 52207177671469202, which contains 22 as substring.

Together with 161566049, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (161566001) 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, 80783025 + 80783026.

It is an arithmetic number, because the mean of its divisors is an integer number (80783026).

Almost surely, 2^161566051 is an apocalyptic number.

161566051 is a deficient number, since it is larger than the sum of its proper divisors (1).

161566051 is an equidigital number, since it uses as much as digits as its factorization.

161566051 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5400, while the sum is 31.

The square root of 161566051 is about 12710.8635033187. The cubic root of 161566051 is about 544.6489909370.

The spelling of 161566051 in words is "one hundred sixty-one million, five hundred sixty-six thousand, fifty-one".