23640140 has 12 divisors (see below), whose sum is σ = 49644336. Its totient is φ = 9456048.

The previous prime is 23640137. The next prime is 23640181. The reversal of 23640140 is 4104632.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1182007 = 23640140 / (2 + 3 + 6 + 4 + 0 + 1 + 4 + 0).

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, 590984 + ... + 591023.

It is an arithmetic number, because the mean of its divisors is an integer number (4137028).

Almost surely, 2^23640140 is an apocalyptic number.

23640140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23640140 is an abundant number, since it is smaller than the sum of its proper divisors (26004196).

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

23640140 is a wasteful number, since it uses less digits than its factorization.

23640140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1182016 (or 1182014 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 23640140 is about 4862.1127095122. The cubic root of 23640140 is about 287.0009590955. Note that the first 3 decimals are identical.

Adding to 23640140 its reverse (4104632), we get a palindrome (27744772).

The spelling of 23640140 in words is "twenty-three million, six hundred forty thousand, one hundred forty".