82665981 has 8 divisors (see below), whose sum is σ = 122468160. Its totient is φ = 55110636.

The previous prime is 82665949. The next prime is 82666013. The reversal of 82665981 is 18956628.

It is an interprime number because it is at equal distance from previous prime (82665949) and next prime (82666013).

It is not a de Polignac number, because 82665981 - 2⁵ = 82665949 is a prime.

It is a super-2 number, since 2×82665981² = 13667328829384722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82665901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1530825 + ... + 1530878.

It is an arithmetic number, because the mean of its divisors is an integer number (15308520).

Almost surely, 2^82665981 is an apocalyptic number.

It is an amenable number.

82665981 is a deficient number, since it is larger than the sum of its proper divisors (39802179).

82665981 is a wasteful number, since it uses less digits than its factorization.

82665981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3061712 (or 3061706 counting only the distinct ones).

The product of its digits is 207360, while the sum is 45.

The square root of 82665981 is about 9092.0834246063. The cubic root of 82665981 is about 435.6211340671.

The spelling of 82665981 in words is "eighty-two million, six hundred sixty-five thousand, nine hundred eighty-one".