20218589664 has 192 divisors, whose sum is σ = 65424360960. Its totient is φ = 5323991040.

The previous prime is 20218589627. The next prime is 20218589731. The reversal of 20218589664 is 46698581202.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 7170847 + ... + 7173665.

It is an arithmetic number, because the mean of its divisors is an integer number (340751880).

Almost surely, 2^20218589664 is an apocalyptic number.

20218589664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20218589664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32712180480).

20218589664 is an abundant number, since it is smaller than the sum of its proper divisors (45205771296).

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

20218589664 is a wasteful number, since it uses less digits than its factorization.

20218589664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3673 (or 3665 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 51.

The spelling of 20218589664 in words is "twenty billion, two hundred eighteen million, five hundred eighty-nine thousand, six hundred sixty-four".