161339904 has 160 divisors (see below), whose sum is σ = 521484480. Its totient is φ = 48844800.

The previous prime is 161339891. The next prime is 161339923. The reversal of 161339904 is 409933161.

161339904 is a `hidden beast` number, since 1 + 613 + 39 + 9 + 0 + 4 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 151534 + ... + 152594.

It is an arithmetic number, because the mean of its divisors is an integer number (3259278).

Almost surely, 2^161339904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161339904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (260742240).

161339904 is an abundant number, since it is smaller than the sum of its proper divisors (360144576).

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

161339904 is a wasteful number, since it uses less digits than its factorization.

161339904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1099 (or 1077 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 161339904 is about 12701.9645724589. The cubic root of 161339904 is about 544.3947538465.

The spelling of 161339904 in words is "one hundred sixty-one million, three hundred thirty-nine thousand, nine hundred four".