20663100 has 90 divisors (see below), whose sum is σ = 67007864. Its totient is φ = 5508000.

The previous prime is 20663087. The next prime is 20663107. The reversal of 20663100 is 136602.

It is a happy number.

20663100 is a `hidden beast` number, since 2 + 0 + 663 + 1 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (90).

It is a super-2 number, since 2×20663100² = 853927403220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20663107) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 6825 + ... + 9375.

Almost surely, 2^20663100 is an apocalyptic number.

20663100 is a gapful number since it is divisible by the number (20) 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 20663100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33503932).

20663100 is an abundant number, since it is smaller than the sum of its proper divisors (46344764).

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

20663100 is a wasteful number, since it uses less digits than its factorization.

20663100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2577 (or 2561 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 20663100 is about 4545.6682677028. The cubic root of 20663100 is about 274.4090893073.

Adding to 20663100 its reverse (136602), we get a palindrome (20799702).

The spelling of 20663100 in words is "twenty million, six hundred sixty-three thousand, one hundred".