18921136677 has 8 divisors (see below), whose sum is σ = 25228871616. Its totient is φ = 12613746432.

The previous prime is 18921136673. The next prime is 18921136721. The reversal of 18921136677 is 77663112981.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18921136677 - 2² = 18921136673 is a prime.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18921136673) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98373 + ... + 217989.

It is an arithmetic number, because the mean of its divisors is an integer number (3153608952).

Almost surely, 2^18921136677 is an apocalyptic number.

It is an amenable number.

18921136677 is a deficient number, since it is larger than the sum of its proper divisors (6307734939).

18921136677 is a wasteful number, since it uses less digits than its factorization.

18921136677 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172347.

The product of its digits is 762048, while the sum is 51.

The spelling of 18921136677 in words is "eighteen billion, nine hundred twenty-one million, one hundred thirty-six thousand, six hundred seventy-seven".