18218620 has 48 divisors (see below), whose sum is σ = 44029440. Its totient is φ = 6202944.

The previous prime is 18218617. The next prime is 18218639. The reversal of 18218620 is 2681281.

It is a super-2 number, since 2×18218620² = 663836229408800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24697 + ... + 25423.

It is an arithmetic number, because the mean of its divisors is an integer number (917280).

Almost surely, 2^18218620 is an apocalyptic number.

18218620 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 18218620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22014720).

18218620 is an abundant number, since it is smaller than the sum of its proper divisors (25810820).

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

18218620 is a wasteful number, since it uses less digits than its factorization.

18218620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 922 (or 920 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 18218620 is about 4268.3275413211. The cubic root of 18218620 is about 263.1308846524.

The spelling of 18218620 in words is "eighteen million, two hundred eighteen thousand, six hundred twenty".