20012021100 has 54 divisors (see below), whose sum is σ = 62726571180. Its totient is φ = 5336538720.

The previous prime is 20012021093. The next prime is 20012021129. The reversal of 20012021100 is 112021002.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 11116890 + ... + 11118689.

It is an arithmetic number, because the mean of its divisors is an integer number (1161603170).

Almost surely, 2^20012021100 is an apocalyptic number.

20012021100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20012021100 is an abundant number, since it is smaller than the sum of its proper divisors (42714550080).

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

20012021100 is a wasteful number, since it uses less digits than its factorization.

20012021100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22235599 (or 22235589 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 20012021100 its reverse (112021002), we get a palindrome (20124042102).

The spelling of 20012021100 in words is "twenty billion, twelve million, twenty-one thousand, one hundred".