18986867221 has 8 divisors (see below), whose sum is σ = 21705841280. Its totient is φ = 16269534288.

The previous prime is 18986867171. The next prime is 18986867267. The reversal of 18986867221 is 12276868981.

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 18986867221 - 2¹⁵ = 18986834453 is a prime.

It is a super-2 number, since 2×18986867221² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18986861221) 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 7 ways as a sum of consecutive naturals, for example, 385386 + ... + 431851.

It is an arithmetic number, because the mean of its divisors is an integer number (2713230160).

Almost surely, 2^18986867221 is an apocalyptic number.

It is an amenable number.

18986867221 is a deficient number, since it is larger than the sum of its proper divisors (2718974059).

18986867221 is an equidigital number, since it uses as much as digits as its factorization.

18986867221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 820563.

The product of its digits is 4644864, while the sum is 58.

The spelling of 18986867221 in words is "eighteen billion, nine hundred eighty-six million, eight hundred sixty-seven thousand, two hundred twenty-one".