161551073 has 2 divisors, whose sum is σ = 161551074. Its totient is φ = 161551072.

The previous prime is 161551069. The next prime is 161551087. The reversal of 161551073 is 370155161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81126049 + 80425024 = 9007^2 + 8968^2 .

It is a cyclic number.

It is not a de Polignac number, because 161551073 - 2² = 161551069 is a prime.

It is not a weakly prime, because it can be changed into another prime (161551063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80775536 + 80775537.

It is an arithmetic number, because the mean of its divisors is an integer number (80775537).

Almost surely, 2^161551073 is an apocalyptic number.

It is an amenable number.

161551073 is a deficient number, since it is larger than the sum of its proper divisors (1).

161551073 is an equidigital number, since it uses as much as digits as its factorization.

161551073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3150, while the sum is 29.

The square root of 161551073 is about 12710.2743086056. The cubic root of 161551073 is about 544.6321598337.

The spelling of 161551073 in words is "one hundred sixty-one million, five hundred fifty-one thousand, seventy-three".