18422172 has 72 divisors (see below), whose sum is σ = 51192960. Its totient is φ = 5559840.

The previous prime is 18422171. The next prime is 18422197. The reversal of 18422172 is 27122481.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18422171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15147 + ... + 16317.

Almost surely, 2^18422172 is an apocalyptic number.

18422172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18422172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25596480).

18422172 is an abundant number, since it is smaller than the sum of its proper divisors (32770788).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18422172 is a wasteful number, since it uses less digits than its factorization.

18422172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1223 (or 1218 counting only the distinct ones).

The product of its digits is 1792, while the sum is 27.

The square root of 18422172 is about 4292.1057768885. The cubic root of 18422172 is about 264.1072222865.

The spelling of 18422172 in words is "eighteen million, four hundred twenty-two thousand, one hundred seventy-two".