23121240 has 32 divisors (see below), whose sum is σ = 69364080. Its totient is φ = 6165632.

The previous prime is 23121209. The next prime is 23121247. The reversal of 23121240 is 4212132.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23121247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96219 + ... + 96458.

Almost surely, 2^23121240 is an apocalyptic number.

23121240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23121240 is an abundant number, since it is smaller than the sum of its proper divisors (46242840).

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

23121240 is a wasteful number, since it uses less digits than its factorization.

23121240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192691 (or 192687 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 23121240 is about 4808.4550533409. The cubic root of 23121240 is about 284.8855188096.

Adding to 23121240 its reverse (4212132), we get a palindrome (27333372).

The spelling of 23121240 in words is "twenty-three million, one hundred twenty-one thousand, two hundred forty".