161085520 has 40 divisors (see below), whose sum is σ = 376500456. Its totient is φ = 64094208.

The previous prime is 161085493. The next prime is 161085527. The reversal of 161085520 is 25580161.

It can be written as a sum of positive squares in 4 ways, for example, as 10679824 + 150405696 = 3268^2 + 12264^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161085527) 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 in 7 ways as a sum of consecutive naturals, for example, 10224 + ... + 20656.

Almost surely, 2^161085520 is an apocalyptic number.

161085520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161085520 is an abundant number, since it is smaller than the sum of its proper divisors (215414936).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161085520 is a wasteful number, since it uses less digits than its factorization.

161085520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10639 (or 10633 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 28.

The square root of 161085520 is about 12691.9470531515. The cubic root of 161085520 is about 544.1084883112.

The spelling of 161085520 in words is "one hundred sixty-one million, eighty-five thousand, five hundred twenty".