18231612 has 48 divisors (see below), whose sum is σ = 49029120. Its totient is φ = 5164992.

The previous prime is 18231601. The next prime is 18231671. The reversal of 18231612 is 21613281.

It is a super-2 number, since 2×18231612² = 664783352237088, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 9814 + ... + 11522.

It is an arithmetic number, because the mean of its divisors is an integer number (1021440).

Almost surely, 2^18231612 is an apocalyptic number.

18231612 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 18231612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24514560).

18231612 is an abundant number, since it is smaller than the sum of its proper divisors (30797508).

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

18231612 is a wasteful number, since it uses less digits than its factorization.

18231612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1850 (or 1848 counting only the distinct ones).

The product of its digits is 576, while the sum is 24.

The square root of 18231612 is about 4269.8491776642. The cubic root of 18231612 is about 263.1934174559.

Adding to 18231612 its reverse (21613281), we get a palindrome (39844893).

The spelling of 18231612 in words is "eighteen million, two hundred thirty-one thousand, six hundred twelve".