161525665 has 32 divisors (see below), whose sum is σ = 232759296. Its totient is φ = 105209280.

The previous prime is 161525659. The next prime is 161525681. The reversal of 161525665 is 566525161.

It is not a de Polignac number, because 161525665 - 2⁵ = 161525633 is a prime.

It is an unprimeable number.

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 in 31 ways as a sum of consecutive naturals, for example, 130600 + ... + 131830.

It is an arithmetic number, because the mean of its divisors is an integer number (7273728).

Almost surely, 2^161525665 is an apocalyptic number.

It is an amenable number.

161525665 is a deficient number, since it is larger than the sum of its proper divisors (71233631).

161525665 is a wasteful number, since it uses less digits than its factorization.

161525665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1429.

The product of its digits is 54000, while the sum is 37.

The square root of 161525665 is about 12709.2747629438. The cubic root of 161525665 is about 544.6036059339.

The spelling of 161525665 in words is "one hundred sixty-one million, five hundred twenty-five thousand, six hundred sixty-five".