82002821 has 4 divisors (see below), whose sum is σ = 82051200. Its totient is φ = 81954444.

The previous prime is 82002793. The next prime is 82002859. The reversal of 82002821 is 12820028.

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 82002821 - 2¹⁸ = 81740677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82002881) 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, 21551 + ... + 25068.

It is an arithmetic number, because the mean of its divisors is an integer number (20512800).

Almost surely, 2^82002821 is an apocalyptic number.

It is an amenable number.

82002821 is a deficient number, since it is larger than the sum of its proper divisors (48379).

82002821 is a wasteful number, since it uses less digits than its factorization.

82002821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48378.

The product of its (nonzero) digits is 512, while the sum is 23.

The square root of 82002821 is about 9055.5409004653. The cubic root of 82002821 is about 434.4531305450.

Adding to 82002821 its reverse (12820028), we get a palindrome (94822849).

The spelling of 82002821 in words is "eighty-two million, two thousand, eight hundred twenty-one".