21212230100 has 36 divisors (see below), whose sum is σ = 46043253564. Its totient is φ = 8482548480.

The previous prime is 21212230099. The next prime is 21212230133. The reversal of 21212230100 is 103221212.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 2531901124 + 18680328976 = 50318^2 + 136676^2 .

It is a congruent number.

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, 360344 + ... + 415056.

Almost surely, 2^21212230100 is an apocalyptic number.

21212230100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21212230100 is an abundant number, since it is smaller than the sum of its proper divisors (24831023464).

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

21212230100 is a wasteful number, since it uses less digits than its factorization.

21212230100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58604 (or 58597 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21212230100 its reverse (103221212), we get a palindrome (21315451312).

The spelling of 21212230100 in words is "twenty-one billion, two hundred twelve million, two hundred thirty thousand, one hundred".