18855693547 has 2 divisors, whose sum is σ = 18855693548. Its totient is φ = 18855693546.

The previous prime is 18855693529. The next prime is 18855693553. The reversal of 18855693547 is 74539655881.

It is a strong prime.

It is an emirp because it is prime and its reverse (74539655881) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18855693547 - 2⁷ = 18855693419 is a prime.

It is not a weakly prime, because it can be changed into another prime (18855693557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9427846773 + 9427846774.

It is an arithmetic number, because the mean of its divisors is an integer number (9427846774).

Almost surely, 2^18855693547 is an apocalyptic number.

18855693547 is a deficient number, since it is larger than the sum of its proper divisors (1).

18855693547 is an equidigital number, since it uses as much as digits as its factorization.

18855693547 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288000, while the sum is 61.

The spelling of 18855693547 in words is "eighteen billion, eight hundred fifty-five million, six hundred ninety-three thousand, five hundred forty-seven".