21221020210100 has 36 divisors (see below), whose sum is σ = 47029392884544. Its totient is φ = 8307803654880.

The previous prime is 21221020210097. The next prime is 21221020210121. The reversal of 21221020210100 is 101202012212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2257550642 + ... + 2257560041.

Almost surely, 2^{21221020210100} is an apocalyptic number.

21221020210100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221020210100 is an abundant number, since it is smaller than the sum of its proper divisors (25808372674444).

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

21221020210100 is a wasteful number, since it uses less digits than its factorization.

21221020210100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4515110744 (or 4515110737 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21221020210100 its reverse (101202012212), we get a palindrome (21322222222312).

The spelling of 21221020210100 in words is "twenty-one trillion, two hundred twenty-one billion, twenty million, two hundred ten thousand, one hundred".