20012111100 has 90 divisors (see below), whose sum is σ = 64871384424. Its totient is φ = 5336560800.

The previous prime is 20012111099. The next prime is 20012111129. The reversal of 20012111100 is 111121002.

It is a happy number.

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

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 1227216 + ... + 1243415.

Almost surely, 2^20012111100 is an apocalyptic number.

20012111100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20012111100 is an abundant number, since it is smaller than the sum of its proper divisors (44859273324).

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

20012111100 is a wasteful number, since it uses less digits than its factorization.

20012111100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2470657 (or 2470641 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 20012111100 its reverse (111121002), we get a palindrome (20123232102).

The spelling of 20012111100 in words is "twenty billion, twelve million, one hundred eleven thousand, one hundred".