21311043100 has 36 divisors (see below), whose sum is σ = 46261492200. Its totient is φ = 8521370560.

The previous prime is 21311043097. The next prime is 21311043119. The reversal of 21311043100 is 134011312.

It is a super-2 number, since 2×21311043100² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 254271 + ... + 327529.

It is an arithmetic number, because the mean of its divisors is an integer number (1285041450).

Almost surely, 2^21311043100 is an apocalyptic number.

21311043100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21311043100 is an abundant number, since it is smaller than the sum of its proper divisors (24950449100).

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

21311043100 is a wasteful number, since it uses less digits than its factorization.

21311043100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76182 (or 76175 counting only the distinct ones).

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

Adding to 21311043100 its reverse (134011312), we get a palindrome (21445054412).

The spelling of 21311043100 in words is "twenty-one billion, three hundred eleven million, forty-three thousand, one hundred".