23121420 has 48 divisors (see below), whose sum is σ = 73989888. Its totient is φ = 5284800.

The previous prime is 23121419. The next prime is 23121421. The reversal of 23121420 is 2412132.

It is an interprime number because it is at equal distance from previous prime (23121419) and next prime (23121421).

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

It is a self number, because there is not a number n which added to its sum of digits gives 23121420.

It is not an unprimeable number, because it can be changed into a prime (23121421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27106 + ... + 27945.

It is an arithmetic number, because the mean of its divisors is an integer number (1541456).

Almost surely, 2^23121420 is an apocalyptic number.

23121420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23121420 is an abundant number, since it is smaller than the sum of its proper divisors (50868468).

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

23121420 is a wasteful number, since it uses less digits than its factorization.

23121420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55070 (or 55068 counting only the distinct ones).

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

The square root of 23121420 is about 4808.4737703350. The cubic root of 23121420 is about 284.8862580903.

Adding to 23121420 its reverse (2412132), we get a palindrome (25533552).

The spelling of 23121420 in words is "twenty-three million, one hundred twenty-one thousand, four hundred twenty".