81411675567881 has 8 divisors (see below), whose sum is σ = 82327810854600. Its totient is φ = 80495571333760.

The previous prime is 81411675567869. The next prime is 81411675567883. The reversal of 81411675567881 is 18876557611418.

It can be written as a sum of positive squares in 4 ways, for example, as 3284373296656 + 78127302271225 = 1812284^2 + 8838965^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81411675567881 is a prime.

It is a super-2 number, since 2×81411675567881² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81411675567883) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2469986 + ... + 12997083.

It is an arithmetic number, because the mean of its divisors is an integer number (10290976356825).

Almost surely, 2^{81411675567881} is an apocalyptic number.

It is an amenable number.

81411675567881 is a deficient number, since it is larger than the sum of its proper divisors (916135286719).

81411675567881 is a wasteful number, since it uses less digits than its factorization.

81411675567881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15526299.

The product of its digits is 90316800, while the sum is 68.

The spelling of 81411675567881 in words is "eighty-one trillion, four hundred eleven billion, six hundred seventy-five million, five hundred sixty-seven thousand, eight hundred eighty-one".