23420440 has 32 divisors (see below), whose sum is σ = 54989280. Its totient is φ = 8960512.

The previous prime is 23420437. The next prime is 23420443. The reversal of 23420440 is 4402432.

It is an interprime number because it is at equal distance from previous prime (23420437) and next prime (23420443).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23420443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11809 + ... + 13648.

It is an arithmetic number, because the mean of its divisors is an integer number (1718415).

Almost surely, 2^23420440 is an apocalyptic number.

23420440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23420440 is an abundant number, since it is smaller than the sum of its proper divisors (31568840).

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

23420440 is a wasteful number, since it uses less digits than its factorization.

23420440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25491 (or 25487 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 19.

The square root of 23420440 is about 4839.4669127911. The cubic root of 23420440 is about 286.1091079621.

Adding to 23420440 its reverse (4402432), we get a palindrome (27822872).

The spelling of 23420440 in words is "twenty-three million, four hundred twenty thousand, four hundred forty".