23405240 has 16 divisors (see below), whose sum is σ = 52661880. Its totient is φ = 9362080.

The previous prime is 23405203. The next prime is 23405257. The reversal of 23405240 is 4250432.

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

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 292526 + ... + 292605.

Almost surely, 2^23405240 is an apocalyptic number.

23405240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23405240 is an abundant number, since it is smaller than the sum of its proper divisors (29256640).

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

23405240 is a wasteful number, since it uses less digits than its factorization.

23405240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 585142 (or 585138 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 20.

The square root of 23405240 is about 4837.8962370022. The cubic root of 23405240 is about 286.0471990826.

Adding to 23405240 its reverse (4250432), we get a palindrome (27655672).

The spelling of 23405240 in words is "twenty-three million, four hundred five thousand, two hundred forty".