21101002021220 has 24 divisors (see below), whose sum is σ = 48340477358208. Its totient is φ = 7673091644000.

The previous prime is 21101002021139. The next prime is 21101002021223. The reversal of 21101002021220 is 2212020010112.

It is a junction number, because it is equal to n+sod(n) for n = 21101002021195 and 21101002021204.

It is not an unprimeable number, because it can be changed into a prime (21101002021223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47956822556 + ... + 47956822995.

It is an arithmetic number, because the mean of its divisors is an integer number (2014186556592).

Almost surely, 2^{21101002021220} is an apocalyptic number.

21101002021220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21101002021220 is an abundant number, since it is smaller than the sum of its proper divisors (27239475336988).

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

21101002021220 is a wasteful number, since it uses less digits than its factorization.

21101002021220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95913645571 (or 95913645569 counting only the distinct ones).

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

Adding to 21101002021220 its reverse (2212020010112), we get a palindrome (23313022031332).

The spelling of 21101002021220 in words is "twenty-one trillion, one hundred one billion, two million, twenty-one thousand, two hundred twenty".