18998451734447 has 2 divisors, whose sum is σ = 18998451734448. Its totient is φ = 18998451734446.

The previous prime is 18998451734429. The next prime is 18998451734489. The reversal of 18998451734447 is 74443715489981.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18998451734447 - 2²⁴ = 18998434957231 is a prime.

It is a super-2 number, since 2×18998451734447² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18998451734147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9499225867223 + 9499225867224.

It is an arithmetic number, because the mean of its divisors is an integer number (9499225867224).

Almost surely, 2^{18998451734447} is an apocalyptic number.

18998451734447 is a deficient number, since it is larger than the sum of its proper divisors (1).

18998451734447 is an equidigital number, since it uses as much as digits as its factorization.

18998451734447 is an evil number, because the sum of its binary digits is even.

The product of its digits is 975421440, while the sum is 74.

The spelling of 18998451734447 in words is "eighteen trillion, nine hundred ninety-eight billion, four hundred fifty-one million, seven hundred thirty-four thousand, four hundred forty-seven".