161565516 has 60 divisors (see below), whose sum is σ = 482708688. Its totient is φ = 46160928.

The previous prime is 161565499. The next prime is 161565517. The reversal of 161565516 is 615565161.

It is a super-2 number, since 2×161565516² = 52206831920692512, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (161565517) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 33351 + ... + 37886.

Almost surely, 2^161565516 is an apocalyptic number.

It is an amenable number.

161565516 is an abundant number, since it is smaller than the sum of its proper divisors (321143172).

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

161565516 is a wasteful number, since it uses less digits than its factorization.

161565516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71260 (or 71249 counting only the distinct ones).

The product of its digits is 27000, while the sum is 36.

The square root of 161565516 is about 12710.8424583109. The cubic root of 161565516 is about 544.6483897638.

The spelling of 161565516 in words is "one hundred sixty-one million, five hundred sixty-five thousand, five hundred sixteen".