123520513 has 4 divisors (see below), whose sum is σ = 123546160. Its totient is φ = 123494868.

The previous prime is 123520499. The next prime is 123520531. The reversal of 123520513 is 315025321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 123520513 - 2¹³ = 123512321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123520583) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3183 + ... + 16036.

It is an arithmetic number, because the mean of its divisors is an integer number (30886540).

Almost surely, 2^123520513 is an apocalyptic number.

It is an amenable number.

123520513 is a deficient number, since it is larger than the sum of its proper divisors (25647).

123520513 is an equidigital number, since it uses as much as digits as its factorization.

123520513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25646.

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 123520513 is about 11113.9782706284. The cubic root of 123520513 is about 498.0195163935.

Adding to 123520513 its reverse (315025321), we get a palindrome (438545834).

The spelling of 123520513 in words is "one hundred twenty-three million, five hundred twenty thousand, five hundred thirteen".