20315123 has 4 divisors (see below), whose sum is σ = 21384360. Its totient is φ = 19245888.

The previous prime is 20315117. The next prime is 20315129. The reversal of 20315123 is 32151302.

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

It is an interprime number because it is at equal distance from previous prime (20315117) and next prime (20315129).

It is a cyclic number.

It is not a de Polignac number, because 20315123 - 2⁸ = 20314867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20315129) 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, 534590 + ... + 534627.

It is an arithmetic number, because the mean of its divisors is an integer number (5346090).

Almost surely, 2^20315123 is an apocalyptic number.

20315123 is a deficient number, since it is larger than the sum of its proper divisors (1069237).

20315123 is a wasteful number, since it uses less digits than its factorization.

20315123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1069236.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 20315123 is about 4507.2300806593. The cubic root of 20315123 is about 272.8599647666.

Adding to 20315123 its reverse (32151302), we get a palindrome (52466425).

The spelling of 20315123 in words is "twenty million, three hundred fifteen thousand, one hundred twenty-three".