23121142420 has 24 divisors (see below), whose sum is σ = 48584869704. Its totient is φ = 9242653056.

The previous prime is 23121142399. The next prime is 23121142469. The reversal of 23121142420 is 2424112132.

It can be written as a sum of positive squares in 4 ways, for example, as 1331716 + 23119810704 = 1154^2 + 152052^2 .

It is a junction number, because it is equal to n+sod(n) for n = 23121142391 and 23121142400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 330007 + ... + 393886.

It is an arithmetic number, because the mean of its divisors is an integer number (2024369571).

Almost surely, 2^23121142420 is an apocalyptic number.

23121142420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23121142420 is an abundant number, since it is smaller than the sum of its proper divisors (25463727284).

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

23121142420 is a wasteful number, since it uses less digits than its factorization.

23121142420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 725499 (or 725497 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 23121142420 its reverse (2424112132), we get a palindrome (25545254552).

The spelling of 23121142420 in words is "twenty-three billion, one hundred twenty-one million, one hundred forty-two thousand, four hundred twenty".