21132123100 has 72 divisors (see below), whose sum is σ = 51750594000. Its totient is φ = 7419417600.

The previous prime is 21132123097. The next prime is 21132123109. The reversal of 21132123100 is 132123112.

It is a super-2 number, since 2×21132123100² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21132123109) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 299325 + ... + 363124.

It is an arithmetic number, because the mean of its divisors is an integer number (718758250).

Almost surely, 2^21132123100 is an apocalyptic number.

21132123100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21132123100 is an abundant number, since it is smaller than the sum of its proper divisors (30618470900).

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

21132123100 is a wasteful number, since it uses less digits than its factorization.

21132123100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 662503 (or 662496 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21132123100 its reverse (132123112), we get a palindrome (21264246212).

The spelling of 21132123100 in words is "twenty-one billion, one hundred thirty-two million, one hundred twenty-three thousand, one hundred".