23403440 has 80 divisors (see below), whose sum is σ = 58255200. Its totient is φ = 8718336.

The previous prime is 23403439. The next prime is 23403451. The reversal of 23403440 is 4430432.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135194 + ... + 135366.

It is an arithmetic number, because the mean of its divisors is an integer number (728190).

Almost surely, 2^23403440 is an apocalyptic number.

23403440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 23403440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29127600).

23403440 is an abundant number, since it is smaller than the sum of its proper divisors (34851760).

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

23403440 is a wasteful number, since it uses less digits than its factorization.

23403440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294 (or 288 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 20.

The square root of 23403440 is about 4837.7102021514. The cubic root of 23403440 is about 286.0398659931.

Adding to 23403440 its reverse (4430432), we get a palindrome (27833872).

The spelling of 23403440 in words is "twenty-three million, four hundred three thousand, four hundred forty".