82821917 has 2 divisors, whose sum is σ = 82821918. Its totient is φ = 82821916.

The previous prime is 82821911. The next prime is 82821961. The reversal of 82821917 is 71912828.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71132356 + 11689561 = 8434^2 + 3419^2 .

It is a cyclic number.

It is not a de Polignac number, because 82821917 - 2⁶ = 82821853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82821911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41410958 + 41410959.

It is an arithmetic number, because the mean of its divisors is an integer number (41410959).

Almost surely, 2^82821917 is an apocalyptic number.

It is an amenable number.

82821917 is a deficient number, since it is larger than the sum of its proper divisors (1).

82821917 is an equidigital number, since it uses as much as digits as its factorization.

82821917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16128, while the sum is 38.

The square root of 82821917 is about 9100.6547566645. The cubic root of 82821917 is about 435.8948716178.

It can be divided in two parts, 82821 and 917, that added together give a palindrome (83738).

The spelling of 82821917 in words is "eighty-two million, eight hundred twenty-one thousand, nine hundred seventeen".