18855897047 has 4 divisors (see below), whose sum is σ = 20306350680. Its totient is φ = 17405443416.

The previous prime is 18855897041. The next prime is 18855897083. The reversal of 18855897047 is 74079855881.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18855897047 - 2⁴ = 18855897031 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 (18855897041) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 725226797 + ... + 725226822.

It is an arithmetic number, because the mean of its divisors is an integer number (5076587670).

Almost surely, 2^18855897047 is an apocalyptic number.

18855897047 is a deficient number, since it is larger than the sum of its proper divisors (1450453633).

18855897047 is a wasteful number, since it uses less digits than its factorization.

18855897047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1450453632.

The product of its (nonzero) digits is 22579200, while the sum is 62.

The spelling of 18855897047 in words is "eighteen billion, eight hundred fifty-five million, eight hundred ninety-seven thousand, forty-seven".