161289904 has 40 divisors (see below), whose sum is σ = 324632000. Its totient is φ = 77571648.

The previous prime is 161289899. The next prime is 161289911. The reversal of 161289904 is 409982161.

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 in 7 ways as a sum of consecutive naturals, for example, 44347 + ... + 47845.

It is an arithmetic number, because the mean of its divisors is an integer number (8115800).

Almost surely, 2^161289904 is an apocalyptic number.

It is an amenable number.

161289904 is an abundant number, since it is smaller than the sum of its proper divisors (163342096).

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

161289904 is a wasteful number, since it uses less digits than its factorization.

161289904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3617 (or 3611 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 40.

The square root of 161289904 is about 12699.9962204719. The cubic root of 161289904 is about 544.3385111990.

The spelling of 161289904 in words is "one hundred sixty-one million, two hundred eighty-nine thousand, nine hundred four".