21310121100 has 36 divisors (see below), whose sum is σ = 61657284584. Its totient is φ = 5682698880.

The previous prime is 21310121071. The next prime is 21310121111. The reversal of 21310121100 is 112101312.

It is a super-2 number, since 2×21310121100² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35516569 + ... + 35517168.

Almost surely, 2^21310121100 is an apocalyptic number.

21310121100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21310121100 is an abundant number, since it is smaller than the sum of its proper divisors (40347163484).

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

21310121100 is a wasteful number, since it uses less digits than its factorization.

21310121100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71033754 (or 71033747 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 12.

Adding to 21310121100 its reverse (112101312), we get a palindrome (21422222412).

The spelling of 21310121100 in words is "twenty-one billion, three hundred ten million, one hundred twenty-one thousand, one hundred".