82001009 has 4 divisors (see below), whose sum is σ = 84828660. Its totient is φ = 79173360.

The previous prime is 82000981. The next prime is 82001057. The reversal of 82001009 is 90010028.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 29757025 + 52243984 = 5455^2 + 7228^2 .

It is a cyclic number.

It is not a de Polignac number, because 82001009 - 2⁸ = 82000753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82001089) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1413782 + ... + 1413839.

It is an arithmetic number, because the mean of its divisors is an integer number (21207165).

Almost surely, 2^82001009 is an apocalyptic number.

It is an amenable number.

82001009 is a deficient number, since it is larger than the sum of its proper divisors (2827651).

82001009 is a wasteful number, since it uses less digits than its factorization.

82001009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2827650.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 82001009 is about 9055.4408506709. The cubic root of 82001009 is about 434.4499305134.

The spelling of 82001009 in words is "eighty-two million, one thousand, nine".