21120123000 has 64 divisors (see below), whose sum is σ = 65894793120. Its totient is φ = 5632032000.

The previous prime is 21120122981. The next prime is 21120123001. The reversal of 21120123000 is 32102112.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120123001) by changing a digit.

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, 3517021 + ... + 3523020.

Almost surely, 2^21120123000 is an apocalyptic number.

21120123000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120123000 is an abundant number, since it is smaller than the sum of its proper divisors (44774670120).

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

21120123000 is a wasteful number, since it uses less digits than its factorization.

21120123000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7040065 (or 7040051 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 21120123000 its reverse (32102112), we get a palindrome (21152225112).

The spelling of 21120123000 in words is "twenty-one billion, one hundred twenty million, one hundred twenty-three thousand".