2161791231 has 8 divisors (see below), whose sum is σ = 2975368704. Its totient is φ = 1394703960.

The previous prime is 2161791227. The next prime is 2161791239. The reversal of 2161791231 is 1321971612.

2161791231 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 2161791231 - 2² = 2161791227 is a prime.

It is a super-2 number, since 2×2161791231² = 9346682652856990722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2161791192 and 2161791201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161791239) 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, 11622441 + ... + 11622626.

It is an arithmetic number, because the mean of its divisors is an integer number (371921088).

Almost surely, 2^2161791231 is an apocalyptic number.

2161791231 is a deficient number, since it is larger than the sum of its proper divisors (813577473).

2161791231 is a wasteful number, since it uses less digits than its factorization.

2161791231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23245101.

The product of its digits is 4536, while the sum is 33.

The square root of 2161791231 is about 46495.0667383111. The cubic root of 2161791231 is about 1293.0180384588.

The spelling of 2161791231 in words is "two billion, one hundred sixty-one million, seven hundred ninety-one thousand, two hundred thirty-one".