74784821 has 2 divisors, whose sum is σ = 74784822. Its totient is φ = 74784820.

The previous prime is 74784793. The next prime is 74784859. The reversal of 74784821 is 12848747.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 69072721 + 5712100 = 8311^2 + 2390^2 .

It is an emirp because it is prime and its reverse (12848747) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 74784821 - 2²⁶ = 7675957 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (74781821) 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 as a sum of consecutive naturals, namely, 37392410 + 37392411.

It is an arithmetic number, because the mean of its divisors is an integer number (37392411).

Almost surely, 2^74784821 is an apocalyptic number.

It is an amenable number.

74784821 is a deficient number, since it is larger than the sum of its proper divisors (1).

74784821 is an equidigital number, since it uses as much as digits as its factorization.

74784821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 100352, while the sum is 41.

The square root of 74784821 is about 8647.8217488568. The cubic root of 74784821 is about 421.3126374467.

The spelling of 74784821 in words is "seventy-four million, seven hundred eighty-four thousand, eight hundred twenty-one".