18319647666 has 16 divisors (see below), whose sum is σ = 36703469088. Its totient is φ = 6095853600.

The previous prime is 18319647649. The next prime is 18319647667. The reversal of 18319647666 is 66674691381.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (18319647667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2670195 + ... + 2677046.

It is an arithmetic number, because the mean of its divisors is an integer number (2293966818).

Almost surely, 2^18319647666 is an apocalyptic number.

18319647666 is an abundant number, since it is smaller than the sum of its proper divisors (18383821422).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18319647666 is a wasteful number, since it uses less digits than its factorization.

18319647666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5347817.

The product of its digits is 7838208, while the sum is 57.

The spelling of 18319647666 in words is "eighteen billion, three hundred nineteen million, six hundred forty-seven thousand, six hundred sixty-six".