161404257 has 32 divisors (see below), whose sum is σ = 250905600. Its totient is φ = 90393408.

The previous prime is 161404253. The next prime is 161404261. The reversal of 161404257 is 752404161.

It is an interprime number because it is at equal distance from previous prime (161404253) and next prime (161404261).

It is not a de Polignac number, because 161404257 - 2² = 161404253 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161404253) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 244594 + ... + 245252.

It is an arithmetic number, because the mean of its divisors is an integer number (7840800).

Almost surely, 2^161404257 is an apocalyptic number.

It is an amenable number.

161404257 is a deficient number, since it is larger than the sum of its proper divisors (89501343).

161404257 is a wasteful number, since it uses less digits than its factorization.

161404257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 885.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 161404257 is about 12704.4975107243. The cubic root of 161404257 is about 544.4671244088.

The spelling of 161404257 in words is "one hundred sixty-one million, four hundred four thousand, two hundred fifty-seven".