161505216 has 84 divisors (see below), whose sum is σ = 465582000. Its totient is φ = 53526528.

The previous prime is 161505181. The next prime is 161505217. The reversal of 161505216 is 612505161.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 161505216.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161505217) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 113920 + ... + 115328.

Almost surely, 2^161505216 is an apocalyptic number.

161505216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161505216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (232791000).

161505216 is an abundant number, since it is smaller than the sum of its proper divisors (304076784).

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

161505216 is a wasteful number, since it uses less digits than its factorization.

161505216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1626 (or 1613 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 27.

The square root of 161505216 is about 12708.4702462570. The cubic root of 161505216 is about 544.5806228595.

The spelling of 161505216 in words is "one hundred sixty-one million, five hundred five thousand, two hundred sixteen".