21120120111020 has 48 divisors (see below), whose sum is σ = 50718879220800. Its totient is φ = 7236813901824.

The previous prime is 21120120110987. The next prime is 21120120111023. The reversal of 21120120111020 is 2011102102112.

It is a super-2 number, since 2×21120120111020² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 21120120110986 and 21120120111004.

It is not an unprimeable number, because it can be changed into a prime (21120120111023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45289445 + ... + 45753404.

It is an arithmetic number, because the mean of its divisors is an integer number (1056643317100).

Almost surely, 2^{21120120111020} is an apocalyptic number.

21120120111020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120120111020 is an abundant number, since it is smaller than the sum of its proper divisors (29598759109780).

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

21120120111020 is a wasteful number, since it uses less digits than its factorization.

21120120111020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91044522 (or 91044520 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21120120111020 its reverse (2011102102112), we get a palindrome (23131222213132).

The spelling of 21120120111020 in words is "twenty-one trillion, one hundred twenty billion, one hundred twenty million, one hundred eleven thousand, twenty".