18339972 has 48 divisors (see below), whose sum is σ = 50491392. Its totient is φ = 5070240.

The previous prime is 18339913. The next prime is 18340019. The reversal of 18339972 is 27993381.

It is a Harshad number since it is a multiple of its sum of digits (42).

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, 918 + ... + 6125.

It is an arithmetic number, because the mean of its divisors is an integer number (1051904).

Almost surely, 2^18339972 is an apocalyptic number.

18339972 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 18339972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25245696).

18339972 is an abundant number, since it is smaller than the sum of its proper divisors (32151420).

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

18339972 is a wasteful number, since it uses less digits than its factorization.

18339972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7088 (or 7086 counting only the distinct ones).

The product of its digits is 81648, while the sum is 42.

The square root of 18339972 is about 4282.5193519703. The cubic root of 18339972 is about 263.7138198240.

The spelling of 18339972 in words is "eighteen million, three hundred thirty-nine thousand, nine hundred seventy-two".