161634520 has 32 divisors (see below), whose sum is σ = 382820400. Its totient is φ = 61250688.

The previous prime is 161634509. The next prime is 161634533. The reversal of 161634520 is 25436161.

It is a super-2 number, since 2×161634520² = 52251436111260800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 105579 + ... + 107098.

Almost surely, 2^161634520 is an apocalyptic number.

161634520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161634520 is an abundant number, since it is smaller than the sum of its proper divisors (221185880).

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

161634520 is a wasteful number, since it uses less digits than its factorization.

161634520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212707 (or 212703 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 161634520 is about 12713.5565440989. The cubic root of 161634520 is about 544.7259177933.

The spelling of 161634520 in words is "one hundred sixty-one million, six hundred thirty-four thousand, five hundred twenty".