81084495491 has 8 divisors (see below), whose sum is σ = 81821776320. Its totient is φ = 80347560832.

The previous prime is 81084495431. The next prime is 81084495563. The reversal of 81084495491 is 19459448018.

It is a happy number.

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-81084495491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81084495431) 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, 396230 + ... + 564948.

It is an arithmetic number, because the mean of its divisors is an integer number (10227722040).

Almost surely, 2^81084495491 is an apocalyptic number.

81084495491 is a deficient number, since it is larger than the sum of its proper divisors (737280829).

81084495491 is a wasteful number, since it uses less digits than its factorization.

81084495491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173085.

The product of its (nonzero) digits is 1658880, while the sum is 53.

The spelling of 81084495491 in words is "eighty-one billion, eighty-four million, four hundred ninety-five thousand, four hundred ninety-one".