82865991 has 8 divisors (see below), whose sum is σ = 118987120. Its totient is φ = 50994432.

The previous prime is 82865989. The next prime is 82866001. The reversal of 82865991 is 19956828.

It is a happy number.

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

It is not a de Polignac number, because 82865991 - 2¹ = 82865989 is a prime.

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 82865991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82865971) 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, 1062346 + ... + 1062423.

It is an arithmetic number, because the mean of its divisors is an integer number (14873390).

Almost surely, 2^82865991 is an apocalyptic number.

82865991 is a deficient number, since it is larger than the sum of its proper divisors (36121129).

82865991 is a wasteful number, since it uses less digits than its factorization.

82865991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2124785.

The product of its digits is 311040, while the sum is 48.

The square root of 82865991 is about 9103.0759087245. The cubic root of 82865991 is about 435.9721789475.

The spelling of 82865991 in words is "eighty-two million, eight hundred sixty-five thousand, nine hundred ninety-one".