161963931 has 8 divisors (see below), whose sum is σ = 216217600. Its totient is φ = 107843112.

The previous prime is 161963831. The next prime is 161963939. The reversal of 161963931 is 139369161.

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

It is not a de Polignac number, because 161963931 - 2⁷ = 161963803 is a prime.

It is a super-2 number, since 2×161963931² = 52464629889945522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161963931.

It is not an unprimeable number, because it can be changed into a prime (161963939) 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, 30331 + ... + 35268.

It is an arithmetic number, because the mean of its divisors is an integer number (27027200).

Almost surely, 2^161963931 is an apocalyptic number.

161963931 is a deficient number, since it is larger than the sum of its proper divisors (54253669).

161963931 is an equidigital number, since it uses as much as digits as its factorization.

161963931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66425.

The product of its digits is 26244, while the sum is 39.

The square root of 161963931 is about 12726.5050583418. The cubic root of 161963931 is about 545.0957169932.

The spelling of 161963931 in words is "one hundred sixty-one million, nine hundred sixty-three thousand, nine hundred thirty-one".