2181252172 has 12 divisors (see below), whose sum is σ = 4164208776. Its totient is φ = 991478240.

The previous prime is 2181252169. The next prime is 2181252209. The reversal of 2181252172 is 2712521812.

It is a super-2 number, since 2×2181252172² = 9515722075709435168, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24786913 + ... + 24787000.

It is an arithmetic number, because the mean of its divisors is an integer number (347017398).

Almost surely, 2^2181252172 is an apocalyptic number.

2181252172 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

2181252172 is a deficient number, since it is larger than the sum of its proper divisors (1982956604).

2181252172 is a wasteful number, since it uses less digits than its factorization.

2181252172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49573928 (or 49573926 counting only the distinct ones).

The product of its digits is 4480, while the sum is 31.

The square root of 2181252172 is about 46703.8774835666. The cubic root of 2181252172 is about 1296.8864684964.

Adding to 2181252172 its reverse (2712521812), we get a palindrome (4893773984).

It can be divided in two parts, 21812 and 52172, that added together give a square (73984 = 272²).

The spelling of 2181252172 in words is "two billion, one hundred eighty-one million, two hundred fifty-two thousand, one hundred seventy-two".