82400321 has 4 divisors (see below), whose sum is σ = 86737200. Its totient is φ = 78063444.

The previous prime is 82400317. The next prime is 82400327. The reversal of 82400321 is 12300428.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 82400321 - 2² = 82400317 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 82400293 and 82400302.

It is not an unprimeable number, because it can be changed into a prime (82400327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2168411 + ... + 2168448.

It is an arithmetic number, because the mean of its divisors is an integer number (21684300).

Almost surely, 2^82400321 is an apocalyptic number.

It is an amenable number.

82400321 is a deficient number, since it is larger than the sum of its proper divisors (4336879).

82400321 is a wasteful number, since it uses less digits than its factorization.

82400321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4336878.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 82400321 is about 9077.4622554985. The cubic root of 82400321 is about 435.1539878484.

Adding to 82400321 its reverse (12300428), we get a palindrome (94700749).

The spelling of 82400321 in words is "eighty-two million, four hundred thousand, three hundred twenty-one".