18443944197 has 12 divisors (see below), whose sum is σ = 30447146080. Its totient is φ = 10539396648.

The previous prime is 18443944187. The next prime is 18443944213. The reversal of 18443944197 is 79144934481.

18443944197 is a `hidden beast` number, since 1 + 8 + 443 + 9 + 4 + 4 + 197 = 666.

It is not a de Polignac number, because 18443944197 - 2⁶ = 18443944133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18443944187) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 146380447 + ... + 146380572.

Almost surely, 2^18443944197 is an apocalyptic number.

It is an amenable number.

18443944197 is a deficient number, since it is larger than the sum of its proper divisors (12003201883).

18443944197 is a wasteful number, since it uses less digits than its factorization.

18443944197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 292761032 (or 292761029 counting only the distinct ones).

The product of its digits is 3483648, while the sum is 54.

The spelling of 18443944197 in words is "eighteen billion, four hundred forty-three million, nine hundred forty-four thousand, one hundred ninety-seven".