161665042 has 16 divisors (see below), whose sum is σ = 302334912. Its totient is φ = 62986320.

The previous prime is 161665039. The next prime is 161665051. The reversal of 161665042 is 240566161.

161665042 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×161665042² = 52271171609723528, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161664995 and 161665013.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 524733 + ... + 525040.

It is an arithmetic number, because the mean of its divisors is an integer number (18895932).

Almost surely, 2^161665042 is an apocalyptic number.

161665042 is a deficient number, since it is larger than the sum of its proper divisors (140669870).

161665042 is a wasteful number, since it uses less digits than its factorization.

161665042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1049793.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 161665042 is about 12714.7568596493. The cubic root of 161665042 is about 544.7602031222.

The spelling of 161665042 in words is "one hundred sixty-one million, six hundred sixty-five thousand, forty-two".