82020581 has 8 divisors (see below), whose sum is σ = 83055000. Its totient is φ = 80990208.

The previous prime is 82020577. The next prime is 82020629. The reversal of 82020581 is 18502028.

It can be written as a sum of positive squares in 4 ways, for example, as 32092225 + 49928356 = 5665^2 + 7066^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 82020581 - 2² = 82020577 is a prime.

It is a super-2 number, since 2×82020581² = 13454751415155122, which contains 22 as substring.

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 82020581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82020571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 65045 + ... + 66293.

It is an arithmetic number, because the mean of its divisors is an integer number (10381875).

Almost surely, 2^82020581 is an apocalyptic number.

It is an amenable number.

82020581 is a deficient number, since it is larger than the sum of its proper divisors (1034419).

82020581 is a wasteful number, since it uses less digits than its factorization.

82020581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2023.

The product of its (nonzero) digits is 1280, while the sum is 26.

The square root of 82020581 is about 9056.5214624601. The cubic root of 82020581 is about 434.4844925988.

The spelling of 82020581 in words is "eighty-two million, twenty thousand, five hundred eighty-one".