18039505705 has 24 divisors (see below), whose sum is σ = 24370298568. Its totient is φ = 12742262016.

The previous prime is 18039505697. The next prime is 18039505721. The reversal of 18039505705 is 50750593081.

It can be written as a sum of positive squares in 4 ways, for example, as 1944016281 + 16095489424 = 44091^2 + 126868^2 .

It is not a de Polignac number, because 18039505705 - 2³ = 18039505697 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 227932 + ... + 296701.

It is an arithmetic number, because the mean of its divisors is an integer number (1015429107).

Almost surely, 2^18039505705 is an apocalyptic number.

It is an amenable number.

18039505705 is a deficient number, since it is larger than the sum of its proper divisors (6330792863).

18039505705 is a wasteful number, since it uses less digits than its factorization.

18039505705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 524697 (or 524674 counting only the distinct ones).

The product of its (nonzero) digits is 189000, while the sum is 43.

The spelling of 18039505705 in words is "eighteen billion, thirty-nine million, five hundred five thousand, seven hundred five".