161639888 has 10 divisors (see below), whose sum is σ = 313177314. Its totient is φ = 80819936.

The previous prime is 161639873. The next prime is 161639899. The reversal of 161639888 is 888936161.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 161594944 + 44944 = 12712^2 + 212^2 .

It is a super-2 number, since 2×161639888² = 52254906785305088, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5051231 + ... + 5051262.

Almost surely, 2^161639888 is an apocalyptic number.

It is an amenable number.

161639888 is a deficient number, since it is larger than the sum of its proper divisors (151537426).

161639888 is a wasteful number, since it uses less digits than its factorization.

161639888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10102501 (or 10102495 counting only the distinct ones).

The product of its digits is 497664, while the sum is 50.

The square root of 161639888 is about 12713.7676555772. The cubic root of 161639888 is about 544.7319479746.

The spelling of 161639888 in words is "one hundred sixty-one million, six hundred thirty-nine thousand, eight hundred eighty-eight".