21202020120 has 128 divisors (see below), whose sum is σ = 63975744000. Its totient is φ = 5621130240.

The previous prime is 21202020097. The next prime is 21202020139. The reversal of 21202020120 is 2102020212.

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 = 21202020096 and 21202020105.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20564005 + ... + 20565035.

It is an arithmetic number, because the mean of its divisors is an integer number (499810500).

Almost surely, 2^21202020120 is an apocalyptic number.

21202020120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21202020120 is an abundant number, since it is smaller than the sum of its proper divisors (42773723880).

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

21202020120 is a wasteful number, since it uses less digits than its factorization.

21202020120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1873 (or 1869 counting only the distinct ones).

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

Adding to 21202020120 its reverse (2102020212), we get a palindrome (23304040332).

The spelling of 21202020120 in words is "twenty-one billion, two hundred two million, twenty thousand, one hundred twenty".