21317698206480 has 1280 divisors, whose sum is σ = 81539101163520. Its totient is φ = 4550728089600.

The previous prime is 21317698206439. The next prime is 21317698206529. The reversal of 21317698206480 is 8460289671312.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21317698206480.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 9114021151 + ... + 9114023489.

It is an arithmetic number, because the mean of its divisors is an integer number (63702422784).

Almost surely, 2^{21317698206480} is an apocalyptic number.

21317698206480 is a gapful number since it is divisible by the number (20) 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 21317698206480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40769550581760).

21317698206480 is an abundant number, since it is smaller than the sum of its proper divisors (60221402957040).

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

21317698206480 is a wasteful number, since it uses less digits than its factorization.

21317698206480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2680 (or 2674 counting only the distinct ones).

The product of its (nonzero) digits is 6967296, while the sum is 57.

The spelling of 21317698206480 in words is "twenty-one trillion, three hundred seventeen billion, six hundred ninety-eight million, two hundred six thousand, four hundred eighty".