21231120120 has 128 divisors (see below), whose sum is σ = 74341324800. Its totient is φ = 4749566976.

The previous prime is 21231120091. The next prime is 21231120121. The reversal of 21231120120 is 2102113212.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21231120120.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231120121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 229405 + ... + 308364.

It is an arithmetic number, because the mean of its divisors is an integer number (580791600).

Almost surely, 2^21231120120 is an apocalyptic number.

21231120120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21231120120 is an abundant number, since it is smaller than the sum of its proper divisors (53110204680).

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

21231120120 is a wasteful number, since it uses less digits than its factorization.

21231120120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 537837 (or 537833 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21231120120 its reverse (2102113212), we get a palindrome (23333233332).

The spelling of 21231120120 in words is "twenty-one billion, two hundred thirty-one million, one hundred twenty thousand, one hundred twenty".