23405520 has 40 divisors (see below), whose sum is σ = 72557856. Its totient is φ = 6241408.

The previous prime is 23405519. The next prime is 23405521. The reversal of 23405520 is 2550432.

It is an interprime number because it is at equal distance from previous prime (23405519) and next prime (23405521).

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23405521) 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, 48522 + ... + 49001.

Almost surely, 2^23405520 is an apocalyptic number.

23405520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23405520 is an abundant number, since it is smaller than the sum of its proper divisors (49152336).

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

23405520 is a wasteful number, since it uses less digits than its factorization.

23405520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97539 (or 97533 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 21.

The square root of 23405520 is about 4837.9251751138. The cubic root of 23405520 is about 286.0483397516.

Adding to 23405520 its reverse (2550432), we get a palindrome (25955952).

The spelling of 23405520 in words is "twenty-three million, four hundred five thousand, five hundred twenty".