18722131 has 8 divisors (see below), whose sum is σ = 19051200. Its totient is φ = 18395520.

The previous prime is 18722113. The next prime is 18722149. The reversal of 18722131 is 13122781.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (18722113) and next prime (18722149).

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

It is a cyclic number.

It is not a de Polignac number, because 18722131 - 2⁷ = 18722003 is a prime.

It is a super-2 number, since 2×18722131² = 701036378362322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18722096 and 18722105.

It is not an unprimeable number, because it can be changed into a prime (18722101) 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, 20811 + ... + 21691.

It is an arithmetic number, because the mean of its divisors is an integer number (2381400).

Almost surely, 2^18722131 is an apocalyptic number.

18722131 is a deficient number, since it is larger than the sum of its proper divisors (329069).

18722131 is an equidigital number, since it uses as much as digits as its factorization.

18722131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1229.

The product of its digits is 672, while the sum is 25.

The square root of 18722131 is about 4326.9077873234. The cubic root of 18722131 is about 265.5329537773.

The spelling of 18722131 in words is "eighteen million, seven hundred twenty-two thousand, one hundred thirty-one".