18680220 has 120 divisors (see below), whose sum is σ = 63179424. Its totient is φ = 4593024.

The previous prime is 18680219. The next prime is 18680231. The reversal of 18680220 is 2208681.

It is a Harshad number since it is a multiple of its sum of digits (27).

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 39 ways as a sum of consecutive naturals, for example, 20617 + ... + 21503.

Almost surely, 2^18680220 is an apocalyptic number.

18680220 is a gapful number since it is divisible by the number (10) 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 18680220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31589712).

18680220 is an abundant number, since it is smaller than the sum of its proper divisors (44499204).

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

18680220 is a wasteful number, since it uses less digits than its factorization.

18680220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 921 (or 910 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 18680220 is about 4322.0620078847. The cubic root of 18680220 is about 265.3346667666.

The spelling of 18680220 in words is "eighteen million, six hundred eighty thousand, two hundred twenty".