81089384281 has 2 divisors, whose sum is σ = 81089384282. Its totient is φ = 81089384280.

The previous prime is 81089384279. The next prime is 81089384339. The reversal of 81089384281 is 18248398018.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 69232134400 + 11857249881 = 263120^2 + 108891^2 .

It is a cyclic number.

It is not a de Polignac number, because 81089384281 - 2¹ = 81089384279 is a prime.

It is a super-2 number, since 2×81089384281² (a number of 23 digits) contains 22 as substring.

Together with 81089384279, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (81089384231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40544692140 + 40544692141.

It is an arithmetic number, because the mean of its divisors is an integer number (40544692141).

Almost surely, 2^81089384281 is an apocalyptic number.

It is an amenable number.

81089384281 is a deficient number, since it is larger than the sum of its proper divisors (1).

81089384281 is an equidigital number, since it uses as much as digits as its factorization.

81089384281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 884736, while the sum is 52.

The spelling of 81089384281 in words is "eighty-one billion, eighty-nine million, three hundred eighty-four thousand, two hundred eighty-one".