18272820 has 48 divisors (see below), whose sum is σ = 52553088. Its totient is φ = 4740480.

The previous prime is 18272809. The next prime is 18272867. The reversal of 18272820 is 2827281.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 1896 + ... + 6335.

It is an arithmetic number, because the mean of its divisors is an integer number (1094856).

Almost surely, 2^18272820 is an apocalyptic number.

18272820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18272820 is an abundant number, since it is smaller than the sum of its proper divisors (34280268).

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

18272820 is a wasteful number, since it uses less digits than its factorization.

18272820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8280 (or 8278 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 30.

The square root of 18272820 is about 4274.6719172353. The cubic root of 18272820 is about 263.3915625474.

The spelling of 18272820 in words is "eighteen million, two hundred seventy-two thousand, eight hundred twenty".