23818640 has 40 divisors (see below), whose sum is σ = 55730808. Its totient is φ = 9466880.

The previous prime is 23818637. The next prime is 23818643. The reversal of 23818640 is 4681832.

It is an interprime number because it is at equal distance from previous prime (23818637) and next prime (23818643).

It can be written as a sum of positive squares in 4 ways, for example, as 9560464 + 14258176 = 3092^2 + 3776^2 .

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

It is a super-2 number, since 2×23818640² = 1134655222899200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 23818597 and 23818606.

It is not an unprimeable number, because it can be changed into a prime (23818643) 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, 12980 + ... + 14700.

Almost surely, 2^23818640 is an apocalyptic number.

23818640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 23818640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27865404).

23818640 is an abundant number, since it is smaller than the sum of its proper divisors (31912168).

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

23818640 is a wasteful number, since it uses less digits than its factorization.

23818640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1907 (or 1901 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 23818640 is about 4880.4344068945. The cubic root of 23818640 is about 287.7215028984.

The spelling of 23818640 in words is "twenty-three million, eight hundred eighteen thousand, six hundred forty".