78824281 has 2 divisors, whose sum is σ = 78824282. Its totient is φ = 78824280.

The previous prime is 78824267. The next prime is 78824287. The reversal of 78824281 is 18242887.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49491225 + 29333056 = 7035^2 + 5416^2 .

It is a cyclic number.

It is not a de Polignac number, because 78824281 - 2²⁵ = 45269849 is a prime.

It is a super-2 number, since 2×78824281² = 12426534550333922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78824287) 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 as a sum of consecutive naturals, namely, 39412140 + 39412141.

It is an arithmetic number, because the mean of its divisors is an integer number (39412141).

Almost surely, 2^78824281 is an apocalyptic number.

It is an amenable number.

78824281 is a deficient number, since it is larger than the sum of its proper divisors (1).

78824281 is an equidigital number, since it uses as much as digits as its factorization.

78824281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 57344, while the sum is 40.

The square root of 78824281 is about 8878.3039483901. The cubic root of 78824281 is about 428.7656705903.

It can be divided in two parts, 7 and 8824281, that added together give a palindrome (8824288).

The spelling of 78824281 in words is "seventy-eight million, eight hundred twenty-four thousand, two hundred eighty-one".