23185513 has 4 divisors (see below), whose sum is σ = 24969028. Its totient is φ = 21402000.

The previous prime is 23185507. The next prime is 23185531. The reversal of 23185513 is 31558132.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10738729 + 12446784 = 3277^2 + 3528^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23185513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23185543) by changing a digit.

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, 891738 + ... + 891763.

It is an arithmetic number, because the mean of its divisors is an integer number (6242257).

Almost surely, 2^23185513 is an apocalyptic number.

It is an amenable number.

23185513 is a deficient number, since it is larger than the sum of its proper divisors (1783515).

23185513 is a wasteful number, since it uses less digits than its factorization.

23185513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1783514.

The product of its digits is 3600, while the sum is 28.

The square root of 23185513 is about 4815.1337468444. The cubic root of 23185513 is about 285.1492518748.

The spelling of 23185513 in words is "twenty-three million, one hundred eighty-five thousand, five hundred thirteen".