21313203366 has 96 divisors (see below), whose sum is σ = 53464416768. Its totient is φ = 5614297920.

The previous prime is 21313203349. The next prime is 21313203367. The reversal of 21313203366 is 66330231312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21313203367) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3708291 + ... + 3714033.

It is an arithmetic number, because the mean of its divisors is an integer number (556921008).

Almost surely, 2^21313203366 is an apocalyptic number.

21313203366 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21313203366, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26732208384).

21313203366 is an abundant number, since it is smaller than the sum of its proper divisors (32151213402).

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

21313203366 is a wasteful number, since it uses less digits than its factorization.

21313203366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6746 (or 6739 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 30.

Adding to 21313203366 its reverse (66330231312), we get a palindrome (87643434678).

The spelling of 21313203366 in words is "twenty-one billion, three hundred thirteen million, two hundred three thousand, three hundred sixty-six".