161518536 has 40 divisors (see below), whose sum is σ = 452403270. Its totient is φ = 53839296.

The previous prime is 161518531. The next prime is 161518573. The reversal of 161518536 is 635815161.

161518536 is a `hidden beast` number, since 1 + 615 + 1 + 8 + 5 + 36 = 666.

It can be written as a sum of positive squares in only one way, i.e., 85932900 + 75585636 = 9270^2 + 8694^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 161518536.

It is not an unprimeable number, because it can be changed into a prime (161518531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 123981 + ... + 125276.

Almost surely, 2^161518536 is an apocalyptic number.

It is an amenable number.

161518536 is an abundant number, since it is smaller than the sum of its proper divisors (290884734).

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

161518536 is a wasteful number, since it uses less digits than its factorization.

161518536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249275 (or 249262 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 161518536 is about 12708.9942953799. The cubic root of 161518536 is about 544.5955937166.

The spelling of 161518536 in words is "one hundred sixty-one million, five hundred eighteen thousand, five hundred thirty-six".