21221112220100 has 72 divisors (see below), whose sum is σ = 51191852345088. Its totient is φ = 7582729910400.

The previous prime is 21221112220031. The next prime is 21221112220109. The reversal of 21221112220100 is 102221112212.

It is not an unprimeable number, because it can be changed into a prime (21221112220109) 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, 263248934 + ... + 263329533.

Almost surely, 2^{21221112220100} is an apocalyptic number.

21221112220100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221112220100 is an abundant number, since it is smaller than the sum of its proper divisors (29970740124988).

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

21221112220100 is a wasteful number, since it uses less digits than its factorization.

21221112220100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 526578525 (or 526578518 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21221112220100 its reverse (102221112212), we get a palindrome (21323333332312).

The spelling of 21221112220100 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twelve million, two hundred twenty thousand, one hundred".