82081819 has 4 divisors (see below), whose sum is σ = 82099944. Its totient is φ = 82063696.

The previous prime is 82081793. The next prime is 82081829. The reversal of 82081819 is 91818028.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-82081819 is a prime.

It is a super-2 number, since 2×82081819² = 13474850020697522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82081829) 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 3 ways as a sum of consecutive naturals, for example, 4239 + ... + 13495.

It is an arithmetic number, because the mean of its divisors is an integer number (20524986).

Almost surely, 2^82081819 is an apocalyptic number.

82081819 is a deficient number, since it is larger than the sum of its proper divisors (18125).

82081819 is an equidigital number, since it uses as much as digits as its factorization.

82081819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18124.

The product of its (nonzero) digits is 9216, while the sum is 37.

The square root of 82081819 is about 9059.9017102836. The cubic root of 82081819 is about 434.5925969389.

The spelling of 82081819 in words is "eighty-two million, eighty-one thousand, eight hundred nineteen".