21202100220 has 48 divisors (see below), whose sum is σ = 67846722048. Its totient is φ = 4846194240.

The previous prime is 21202100207. The next prime is 21202100267. The reversal of 21202100220 is 2200120212.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21202100196 and 21202100205.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25240176 + ... + 25241015.

It is an arithmetic number, because the mean of its divisors is an integer number (1413473376).

Almost surely, 2^21202100220 is an apocalyptic number.

21202100220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21202100220 is an abundant number, since it is smaller than the sum of its proper divisors (46644621828).

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

21202100220 is a wasteful number, since it uses less digits than its factorization.

21202100220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50481210 (or 50481208 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21202100220 its reverse (2200120212), we get a palindrome (23402220432).

The spelling of 21202100220 in words is "twenty-one billion, two hundred two million, one hundred thousand, two hundred twenty".