18855436551 has 16 divisors (see below), whose sum is σ = 28735776000. Its totient is φ = 10773154368.

The previous prime is 18855436549. The next prime is 18855436631. The reversal of 18855436551 is 15563455881.

It is a happy number.

It is not a de Polignac number, because 18855436551 - 2¹ = 18855436549 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18855436494 and 18855436503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18855436651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 123475 + ... + 230123.

It is an arithmetic number, because the mean of its divisors is an integer number (1795986000).

Almost surely, 2^18855436551 is an apocalyptic number.

18855436551 is a deficient number, since it is larger than the sum of its proper divisors (9880339449).

18855436551 is a wasteful number, since it uses less digits than its factorization.

18855436551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115078.

The product of its digits is 2880000, while the sum is 51.

The spelling of 18855436551 in words is "eighteen billion, eight hundred fifty-five million, four hundred thirty-six thousand, five hundred fifty-one".