21213300100 has 18 divisors (see below), whose sum is σ = 46032861434. Its totient is φ = 8485320000.

The previous prime is 21213300091. The next prime is 21213300109. The reversal of 21213300100 is 100331212.

It is an interprime number because it is at equal distance from previous prime (21213300091) and next prime (21213300109).

It can be written as a sum of positive squares in 3 ways, for example, as 4309659904 + 16903640196 = 65648^2 + 130014^2 .

It is a super-2 number, since 2×21213300100² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21213300109) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 106066401 + ... + 106066600.

Almost surely, 2^21213300100 is an apocalyptic number.

21213300100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21213300100 is an abundant number, since it is smaller than the sum of its proper divisors (24819561334).

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

21213300100 is a wasteful number, since it uses less digits than its factorization.

21213300100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212133015 (or 212133008 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21213300100 its reverse (100331212), we get a palindrome (21313631312).

The spelling of 21213300100 in words is "twenty-one billion, two hundred thirteen million, three hundred thousand, one hundred".