161239680 has 512 divisors, whose sum is σ = 689356800. Its totient is φ = 34836480.

The previous prime is 161239619. The next prime is 161239697. The reversal of 161239680 is 86932161.

161239680 is a `hidden beast` number, since 1 + 612 + 39 + 6 + 8 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3749739 + ... + 3749781.

It is an arithmetic number, because the mean of its divisors is an integer number (1346400).

Almost surely, 2^161239680 is an apocalyptic number.

161239680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161239680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (344678400).

161239680 is an abundant number, since it is smaller than the sum of its proper divisors (528117120).

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

161239680 is a wasteful number, since it uses less digits than its factorization.

161239680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109 (or 91 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 161239680 is about 12698.0187430953. The cubic root of 161239680 is about 544.2820048816.

The spelling of 161239680 in words is "one hundred sixty-one million, two hundred thirty-nine thousand, six hundred eighty".