23515140 has 144 divisors (see below), whose sum is σ = 75075840. Its totient is φ = 5491200.

The previous prime is 23515117. The next prime is 23515147. The reversal of 23515140 is 4151532.

It is not an unprimeable number, because it can be changed into a prime (23515147) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 297621 + ... + 297699.

It is an arithmetic number, because the mean of its divisors is an integer number (521360).

Almost surely, 2^23515140 is an apocalyptic number.

23515140 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 23515140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37537920).

23515140 is an abundant number, since it is smaller than the sum of its proper divisors (51560700).

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

23515140 is a wasteful number, since it uses less digits than its factorization.

23515140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154 (or 141 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 23515140 is about 4849.2411777514. The cubic root of 23515140 is about 286.4942145276.

Adding to 23515140 its reverse (4151532), we get a palindrome (27666672).

The spelling of 23515140 in words is "twenty-three million, five hundred fifteen thousand, one hundred forty".