23121000000 has 588 divisors, whose sum is σ = 94931284864. Its totient is φ = 5270400000.

The previous prime is 23120999959. The next prime is 23121000011. The reversal of 23121000000 is 12132.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 62999817 + ... + 63000183.

Almost surely, 2^23121000000 is an apocalyptic number.

23121000000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 23121000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47465642432).

23121000000 is an abundant number, since it is smaller than the sum of its proper divisors (71810284864).

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

23121000000 is an frugal number, since it uses more digits than its factorization.

23121000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422 (or 384 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

Adding to 23121000000 its reverse (12132), we get a palindrome (23121012132).

The spelling of 23121000000 in words is "twenty-three billion, one hundred twenty-one million", and thus it is an aban number.