161608731 has 8 divisors (see below), whose sum is σ = 215847744. Its totient is φ = 107554440.

The previous prime is 161608723. The next prime is 161608747. The reversal of 161608731 is 137806161.

161608731 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 161608731 - 2³ = 161608723 is a prime.

It is a super-2 number, since 2×161608731² = 52234763870860722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161608692 and 161608701.

It is not an unprimeable number, because it can be changed into a prime (161608771) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44125 + ... + 47646.

It is an arithmetic number, because the mean of its divisors is an integer number (26980968).

Almost surely, 2^161608731 is an apocalyptic number.

161608731 is a deficient number, since it is larger than the sum of its proper divisors (54239013).

161608731 is an equidigital number, since it uses as much as digits as its factorization.

161608731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92361.

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 161608731 is about 12712.5422713162. The cubic root of 161608731 is about 544.6969456738.

The spelling of 161608731 in words is "one hundred sixty-one million, six hundred eight thousand, seven hundred thirty-one".