20217415680 has 1296 divisors, whose sum is σ = 92014993980. Its totient is φ = 4087480320.

The previous prime is 20217415619. The next prime is 20217415681. The reversal of 20217415680 is 8651471202.

20217415680 is a `hidden beast` number, since 2 + 0 + 21 + 74 + 1 + 568 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 19725640704 + 491774976 = 140448^2 + 22176^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (20217415681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 546416622 + ... + 546416658.

Almost surely, 2^20217415680 is an apocalyptic number.

20217415680 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 20217415680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46007496990).

20217415680 is an abundant number, since it is smaller than the sum of its proper divisors (71797578300).

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

20217415680 is a wasteful number, since it uses less digits than its factorization.

20217415680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

Adding to 20217415680 its reverse (8651471202), we get a palindrome (28868886882).

The spelling of 20217415680 in words is "twenty billion, two hundred seventeen million, four hundred fifteen thousand, six hundred eighty".