6581771997696 has 840 divisors, whose sum is σ = 24286448698380. Its totient is φ = 1769804660736.

The previous prime is 6581771997667. The next prime is 6581771997701. The reversal of 6581771997696 is 6967991771856.

It can be written as a sum of positive squares in 2 ways, for example, as 5295815997696 + 1285956000000 = 2301264^2 + 1134000^2 .

It is a Harshad number since it is a multiple of its sum of digits (81).

It is an unprimeable number.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 310905000 + ... + 310926168.

Almost surely, 2^{6581771997696} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6581771997696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12143224349190).

6581771997696 is an abundant number, since it is smaller than the sum of its proper divisors (17704676700684).

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

6581771997696 is an equidigital number, since it uses as much as digits as its factorization.

6581771997696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21236 (or 21198 counting only the distinct ones).

The product of its digits is 2160406080, while the sum is 81.

The spelling of 6581771997696 in words is "six trillion, five hundred eighty-one billion, seven hundred seventy-one million, nine hundred ninety-seven thousand, six hundred ninety-six".