20439918123 has 4 divisors (see below), whose sum is σ = 27253224168. Its totient is φ = 13626612080.

The previous prime is 20439918113. The next prime is 20439918133. The reversal of 20439918123 is 32181993402.

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 (20439918113) and next prime (20439918133).

It is a cyclic number.

It is not a de Polignac number, because 20439918123 - 2¹⁷ = 20439787051 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20439918113) 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, 3406653018 + ... + 3406653023.

It is an arithmetic number, because the mean of its divisors is an integer number (6813306042).

Almost surely, 2^20439918123 is an apocalyptic number.

20439918123 is a deficient number, since it is larger than the sum of its proper divisors (6813306045).

20439918123 is an equidigital number, since it uses as much as digits as its factorization.

20439918123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6813306044.

The product of its (nonzero) digits is 93312, while the sum is 42.

The spelling of 20439918123 in words is "twenty billion, four hundred thirty-nine million, nine hundred eighteen thousand, one hundred twenty-three".