20686117480 has 256 divisors, whose sum is σ = 57699164160. Its totient is φ = 6513868800.

The previous prime is 20686117421. The next prime is 20686117481. The reversal of 20686117480 is 8471168602.

It is not an unprimeable number, because it can be changed into a prime (20686117481) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 55458574 + ... + 55458946.

It is an arithmetic number, because the mean of its divisors is an integer number (225387360).

Almost surely, 2^20686117480 is an apocalyptic number.

20686117480 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 20686117480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28849582080).

20686117480 is an abundant number, since it is smaller than the sum of its proper divisors (37013046680).

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

20686117480 is a wasteful number, since it uses less digits than its factorization.

20686117480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 660 (or 656 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 43.

The spelling of 20686117480 in words is "twenty billion, six hundred eighty-six million, one hundred seventeen thousand, four hundred eighty".