161031390 has 32 divisors (see below), whose sum is σ = 416205216. Its totient is φ = 39638400.

The previous prime is 161031389. The next prime is 161031419. The reversal of 161031390 is 93130161.

161031390 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×161031390² = 51862217130664200, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 161031390.

It is a congruent number.

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, 206061 + ... + 206840.

It is an arithmetic number, because the mean of its divisors is an integer number (13006413).

Almost surely, 2^161031390 is an apocalyptic number.

161031390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161031390 is an abundant number, since it is smaller than the sum of its proper divisors (255173826).

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

161031390 is a wasteful number, since it uses less digits than its factorization.

161031390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 412924.

The product of its (nonzero) digits is 486, while the sum is 24.

The square root of 161031390 is about 12689.8144194468. The cubic root of 161031390 is about 544.0475354043.

The spelling of 161031390 in words is "one hundred sixty-one million, thirty-one thousand, three hundred ninety".