21200120220 has 48 divisors (see below), whose sum is σ = 59367103488. Its totient is φ = 5652720960.

The previous prime is 21200120213. The next prime is 21200120237. The reversal of 21200120220 is 2202100212.

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 = 21200120196 and 21200120205.

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 15 ways as a sum of consecutive naturals, for example, 760977 + ... + 788343.

It is an arithmetic number, because the mean of its divisors is an integer number (1236814656).

Almost surely, 2^21200120220 is an apocalyptic number.

21200120220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21200120220 is an abundant number, since it is smaller than the sum of its proper divisors (38166983268).

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

21200120220 is a wasteful number, since it uses less digits than its factorization.

21200120220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40290 (or 40288 counting only the distinct ones).

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

Adding to 21200120220 its reverse (2202100212), we get a palindrome (23402220432).

It can be divided in two parts, 212001 and 20220, that added together give a triangular number (232221 = T₆₈₁).

The spelling of 21200120220 in words is "twenty-one billion, two hundred million, one hundred twenty thousand, two hundred twenty".