161609818 has 8 divisors (see below), whose sum is σ = 243337248. Its totient is φ = 80497404.

The previous prime is 161609771. The next prime is 161609863. The reversal of 161609818 is 818906161.

161609818 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×161609818² = 52235466547986248, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 153096 + ... + 154147.

It is an arithmetic number, because the mean of its divisors is an integer number (30417156).

Almost surely, 2^161609818 is an apocalyptic number.

161609818 is a deficient number, since it is larger than the sum of its proper divisors (81727430).

161609818 is a wasteful number, since it uses less digits than its factorization.

161609818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307508.

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 161609818 is about 12712.5850242978. The cubic root of 161609818 is about 544.6981669037.

The spelling of 161609818 in words is "one hundred sixty-one million, six hundred nine thousand, eight hundred eighteen".