18638100 has 216 divisors, whose sum is σ = 66349920. Its totient is φ = 4510080.

The previous prime is 18638089. The next prime is 18638101. The reversal of 18638100 is 183681.

18638100 is a `hidden beast` number, since 18 + 638 + 10 + 0 = 666.

It is a super-2 number, since 2×18638100² = 694757543220000, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18638101) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 315871 + ... + 315929.

Almost surely, 2^18638100 is an apocalyptic number.

18638100 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 18638100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33174960).

18638100 is an abundant number, since it is smaller than the sum of its proper divisors (47711820).

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

18638100 is a wasteful number, since it uses less digits than its factorization.

18638100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101 (or 82 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 18638100 is about 4317.1865838761. The cubic root of 18638100 is about 265.1350919137.

The spelling of 18638100 in words is "eighteen million, six hundred thirty-eight thousand, one hundred".