81717586289284 has 27 divisors (see below), whose sum is σ = 157188549563031. Its totient is φ = 37144267006440.

The previous prime is 81717586289281. The next prime is 81717586289321. The reversal of 81717586289284 is 48298268571718.

The square root of 81717586289284 is 9039778.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81717586289284.

It is not an unprimeable number, because it can be changed into a prime (81717586289281) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 198669667 + ... + 199080565.

Almost surely, 2^{81717586289284} is an apocalyptic number.

81717586289284 is the 9039778-th square number.

It is an amenable number.

81717586289284 is a deficient number, since it is larger than the sum of its proper divisors (75470963273747).

81717586289284 is an frugal number, since it uses more digits than its factorization.

81717586289284 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 821824 (or 410912 counting only the distinct ones).

The product of its digits is 867041280, while the sum is 76.

The spelling of 81717586289284 in words is "eighty-one trillion, seven hundred seventeen billion, five hundred eighty-six million, two hundred eighty-nine thousand, two hundred eighty-four".