18211361663 has 8 divisors (see below), whose sum is σ = 19930824576. Its totient is φ = 16502546200.

The previous prime is 18211361627. The next prime is 18211361669. The reversal of 18211361663 is 36616311281.

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 18211361663 - 2⁶ = 18211361599 is a prime.

It is a super-2 number, since 2×18211361663² (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 (18211361669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2658281 + ... + 2665122.

It is an arithmetic number, because the mean of its divisors is an integer number (2491353072).

Almost surely, 2^18211361663 is an apocalyptic number.

18211361663 is a deficient number, since it is larger than the sum of its proper divisors (1719462913).

18211361663 is a wasteful number, since it uses less digits than its factorization.

18211361663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5323725.

The product of its digits is 31104, while the sum is 38.

The spelling of 18211361663 in words is "eighteen billion, two hundred eleven million, three hundred sixty-one thousand, six hundred sixty-three".