2172985881 has 24 divisors (see below), whose sum is σ = 3323127360. Its totient is φ = 1259697120.

The previous prime is 2172985879. The next prime is 2172985891. The reversal of 2172985881 is 1885892712.

It is not a de Polignac number, because 2172985881 - 2¹ = 2172985879 is a prime.

It is a super-2 number, since 2×2172985881² = 9443735278050692322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2172985861) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 121786 + ... + 138483.

It is an arithmetic number, because the mean of its divisors is an integer number (138463640).

Almost surely, 2^2172985881 is an apocalyptic number.

It is an amenable number.

2172985881 is a deficient number, since it is larger than the sum of its proper divisors (1150141479).

2172985881 is a wasteful number, since it uses less digits than its factorization.

2172985881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260317 (or 260306 counting only the distinct ones).

The product of its digits is 645120, while the sum is 51.

The square root of 2172985881 is about 46615.2966417677. The cubic root of 2172985881 is about 1295.2461244649.

The spelling of 2172985881 in words is "two billion, one hundred seventy-two million, nine hundred eighty-five thousand, eight hundred eighty-one".