18221396893 has 8 divisors (see below), whose sum is σ = 20952212288. Its totient is φ = 15522521184.

The previous prime is 18221396867. The next prime is 18221396939. The reversal of 18221396893 is 39869312281.

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 18221396893 - 2⁵ = 18221396861 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18221396893.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18221396863) 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, 7983696 + ... + 7985977.

It is an arithmetic number, because the mean of its divisors is an integer number (2619026536).

Almost surely, 2^18221396893 is an apocalyptic number.

It is an amenable number.

18221396893 is a deficient number, since it is larger than the sum of its proper divisors (2730815395).

18221396893 is a wasteful number, since it uses less digits than its factorization.

18221396893 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15969843.

The product of its digits is 1119744, while the sum is 52.

The spelling of 18221396893 in words is "eighteen billion, two hundred twenty-one million, three hundred ninety-six thousand, eight hundred ninety-three".