20726447680 has 28 divisors (see below), whose sum is σ = 49354854300. Its totient is φ = 8290578944.

The previous prime is 20726447659. The next prime is 20726447681. The reversal of 20726447680 is 8674462702.

It can be written as a sum of positive squares in 2 ways, for example, as 6166646784 + 14559800896 = 78528^2 + 120664^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20726447680.

It is not an unprimeable number, because it can be changed into a prime (20726447681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32384755 + ... + 32385394.

Almost surely, 2^20726447680 is an apocalyptic number.

20726447680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20726447680 is an abundant number, since it is smaller than the sum of its proper divisors (28628406620).

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

20726447680 is an equidigital number, since it uses as much as digits as its factorization.

20726447680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64770166 (or 64770156 counting only the distinct ones).

The product of its (nonzero) digits is 903168, while the sum is 46.

The spelling of 20726447680 in words is "twenty billion, seven hundred twenty-six million, four hundred forty-seven thousand, six hundred eighty".