23121340 has 24 divisors (see below), whose sum is σ = 52969392. Its totient is φ = 8407680.

The previous prime is 23121331. The next prime is 23121341. The reversal of 23121340 is 4312132.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23121341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52329 + ... + 52768.

It is an arithmetic number, because the mean of its divisors is an integer number (2207058).

Almost surely, 2^23121340 is an apocalyptic number.

23121340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23121340 is an abundant number, since it is smaller than the sum of its proper divisors (29848052).

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

23121340 is a wasteful number, since it uses less digits than its factorization.

23121340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105117 (or 105115 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 23121340 is about 4808.4654516800. The cubic root of 23121340 is about 284.8859295215.

Adding to 23121340 its reverse (4312132), we get a palindrome (27433472).

The spelling of 23121340 in words is "twenty-three million, one hundred twenty-one thousand, three hundred forty".