18209880 has 128 divisors (see below), whose sum is σ = 65419200. Its totient is φ = 4478976.

The previous prime is 18209879. The next prime is 18209897. The reversal of 18209880 is 8890281.

It is a super-2 number, since 2×18209880² = 663199459228800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13392 + ... + 14688.

Almost surely, 2^18209880 is an apocalyptic number.

18209880 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 18209880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32709600).

18209880 is an abundant number, since it is smaller than the sum of its proper divisors (47209320).

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

18209880 is a wasteful number, since it uses less digits than its factorization.

18209880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1330 (or 1320 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 36.

The square root of 18209880 is about 4267.3035982925. The cubic root of 18209880 is about 263.0888007517.

The spelling of 18209880 in words is "eighteen million, two hundred nine thousand, eight hundred eighty".