23205640 has 32 divisors (see below), whose sum is σ = 52954560. Its totient is φ = 9150400.

The previous prime is 23205619. The next prime is 23205641. The reversal of 23205640 is 4650232.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (23205641) 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, 1246 + ... + 6925.

It is an arithmetic number, because the mean of its divisors is an integer number (1654830).

Almost surely, 2^23205640 is an apocalyptic number.

23205640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23205640 is an abundant number, since it is smaller than the sum of its proper divisors (29748920).

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

23205640 is a wasteful number, since it uses less digits than its factorization.

23205640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8253 (or 8249 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 23205640 is about 4817.2232665717. The cubic root of 23205640 is about 285.2317392897.

Adding to 23205640 its reverse (4650232), we get a palindrome (27855872).

The spelling of 23205640 in words is "twenty-three million, two hundred five thousand, six hundred forty".