81582986 has 8 divisors (see below), whose sum is σ = 124380804. Its totient is φ = 40122720.

The previous prime is 81582971. The next prime is 81583027. The reversal of 81582986 is 68928518.

It can be written as a sum of positive squares in 2 ways, for example, as 81558961 + 24025 = 9031^2 + 155^2 .

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 81582986.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 334235 + ... + 334478.

Almost surely, 2^81582986 is an apocalyptic number.

81582986 is a deficient number, since it is larger than the sum of its proper divisors (42797818).

81582986 is a wasteful number, since it uses less digits than its factorization.

81582986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 668776.

The product of its digits is 276480, while the sum is 47.

The square root of 81582986 is about 9032.3300426856. The cubic root of 81582986 is about 433.7104292758.

The spelling of 81582986 in words is "eighty-one million, five hundred eighty-two thousand, nine hundred eighty-six".