20115100 has 18 divisors (see below), whose sum is σ = 43649984. Its totient is φ = 8046000.

The previous prime is 20115083. The next prime is 20115101. The reversal of 20115100 is 151102.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20115101) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 100476 + ... + 100675.

Almost surely, 2^20115100 is an apocalyptic number.

20115100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20115100 is an abundant number, since it is smaller than the sum of its proper divisors (23534884).

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

20115100 is a wasteful number, since it uses less digits than its factorization.

20115100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201165 (or 201158 counting only the distinct ones).

The product of its (nonzero) digits is 10, while the sum is 10.

The square root of 20115100 is about 4484.9860646383. The cubic root of 20115100 is about 271.9614817140.

Adding to 20115100 its reverse (151102), we get a palindrome (20266202).

The spelling of 20115100 in words is "twenty million, one hundred fifteen thousand, one hundred".