18644890936321 has 8 divisors (see below), whose sum is σ = 20119032037440. Its totient is φ = 17176452509712.

The previous prime is 18644890936267. The next prime is 18644890936327. The reversal of 18644890936321 is 12363909844681.

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

It is a cyclic number.

It is not a de Polignac number, because 18644890936321 - 2⁹ = 18644890935809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18644890936327) 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, 1425661831 + ... + 1425674908.

It is an arithmetic number, because the mean of its divisors is an integer number (2514879004680).

Almost surely, 2^{18644890936321} is an apocalyptic number.

It is an amenable number.

18644890936321 is a deficient number, since it is larger than the sum of its proper divisors (1474141101119).

18644890936321 is a wasteful number, since it uses less digits than its factorization.

18644890936321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2851337255.

The product of its (nonzero) digits is 53747712, while the sum is 64.

The spelling of 18644890936321 in words is "eighteen trillion, six hundred forty-four billion, eight hundred ninety million, nine hundred thirty-six thousand, three hundred twenty-one".