161564887 has 24 divisors (see below), whose sum is σ = 188359920. Its totient is φ = 138230400.

The previous prime is 161564881. The next prime is 161564891. The reversal of 161564887 is 788465161.

It is not a de Polignac number, because 161564887 - 2⁷ = 161564759 is a prime.

It is a super-2 number, since 2×161564887² = 52206425422645538, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161564881) by changing a digit.

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 in 23 ways as a sum of consecutive naturals, for example, 143308 + ... + 144430.

It is an arithmetic number, because the mean of its divisors is an integer number (7848330).

Almost surely, 2^161564887 is an apocalyptic number.

161564887 is a deficient number, since it is larger than the sum of its proper divisors (26795033).

161564887 is a wasteful number, since it uses less digits than its factorization.

161564887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1215 (or 1204 counting only the distinct ones).

The product of its digits is 322560, while the sum is 46.

The square root of 161564887 is about 12710.8177156310. The cubic root of 161564887 is about 544.6476829623.

The spelling of 161564887 in words is "one hundred sixty-one million, five hundred sixty-four thousand, eight hundred eighty-seven".