18445640305 has 24 divisors (see below), whose sum is σ = 24271960320. Its totient is φ = 13440433920.

The previous prime is 18445640293. The next prime is 18445640329. The reversal of 18445640305 is 50304654481.

It is a happy number.

It is not a de Polignac number, because 18445640305 - 2⁵ = 18445640273 is a prime.

It is a super-2 number, since 2×18445640305² (a number of 21 digits) contains 22 as substring.

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, 161095 + ... + 250684.

It is an arithmetic number, because the mean of its divisors is an integer number (1011331680).

Almost surely, 2^18445640305 is an apocalyptic number.

It is an amenable number.

18445640305 is a deficient number, since it is larger than the sum of its proper divisors (5826320015).

18445640305 is a wasteful number, since it uses less digits than its factorization.

18445640305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 411849 (or 411832 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 40.

The spelling of 18445640305 in words is "eighteen billion, four hundred forty-five million, six hundred forty thousand, three hundred five".