245815123 has 4 divisors (see below), whose sum is σ = 251045280. Its totient is φ = 240584968.

The previous prime is 245815117. The next prime is 245815139. The reversal of 245815123 is 321518542.

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

It is a cyclic number.

It is not a de Polignac number, because 245815123 - 2⁵ = 245815091 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (245815153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2615008 + ... + 2615101.

It is an arithmetic number, because the mean of its divisors is an integer number (62761320).

Almost surely, 2^245815123 is an apocalyptic number.

245815123 is a deficient number, since it is larger than the sum of its proper divisors (5230157).

245815123 is an equidigital number, since it uses as much as digits as its factorization.

245815123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5230156.

The product of its digits is 9600, while the sum is 31.

The square root of 245815123 is about 15678.4923701228. The cubic root of 245815123 is about 626.4256505203.

The spelling of 245815123 in words is "two hundred forty-five million, eight hundred fifteen thousand, one hundred twenty-three".