18021944147 has 16 divisors (see below), whose sum is σ = 19701921792. Its totient is φ = 16433271360.

The previous prime is 18021944119. The next prime is 18021944159. The reversal of 18021944147 is 74144912081.

It is a cyclic number.

It is not a de Polignac number, because 18021944147 - 2²⁸ = 17753508691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18021944947) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 140858 + ... + 236399.

It is an arithmetic number, because the mean of its divisors is an integer number (1231370112).

Almost surely, 2^18021944147 is an apocalyptic number.

18021944147 is a deficient number, since it is larger than the sum of its proper divisors (1679977645).

18021944147 is a wasteful number, since it uses less digits than its factorization.

18021944147 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377378.

The product of its (nonzero) digits is 64512, while the sum is 41.

The spelling of 18021944147 in words is "eighteen billion, twenty-one million, nine hundred forty-four thousand, one hundred forty-seven".