23220640 has 48 divisors (see below), whose sum is σ = 58092552. Its totient is φ = 8740864.

The previous prime is 23220601. The next prime is 23220649. The reversal of 23220640 is 4602232.

It can be written as a sum of positive squares in 4 ways, for example, as 23001616 + 219024 = 4796^2 + 468^2 .

It is not an unprimeable number, because it can be changed into a prime (23220649) 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, 1549 + ... + 6988.

Almost surely, 2^23220640 is an apocalyptic number.

23220640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23220640 is an abundant number, since it is smaller than the sum of its proper divisors (34871912).

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

23220640 is a wasteful number, since it uses less digits than its factorization.

23220640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8569 (or 8561 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 23220640 is about 4818.7799285711. The cubic root of 23220640 is about 285.2931834696.

Adding to 23220640 its reverse (4602232), we get a palindrome (27822872).

The spelling of 23220640 in words is "twenty-three million, two hundred twenty thousand, six hundred forty".