161638960 has 80 divisors (see below), whose sum is σ = 443400192. Its totient is φ = 53625600.

The previous prime is 161638943. The next prime is 161639003. The reversal of 161638960 is 69836161.

161638960 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×161638960² = 52254306779763200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12705 + ... + 22015.

Almost surely, 2^161638960 is an apocalyptic number.

161638960 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 161638960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (221700096).

161638960 is an abundant number, since it is smaller than the sum of its proper divisors (281761232).

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

161638960 is a wasteful number, since it uses less digits than its factorization.

161638960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9362 (or 9356 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 161638960 is about 12713.7311596557. The cubic root of 161638960 is about 544.7309055086.

The spelling of 161638960 in words is "one hundred sixty-one million, six hundred thirty-eight thousand, nine hundred sixty".