74481821 has 2 divisors, whose sum is σ = 74481822. Its totient is φ = 74481820.

The previous prime is 74481779. The next prime is 74481829. The reversal of 74481821 is 12818447.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 69122596 + 5359225 = 8314^2 + 2315^2 .

It is an emirp because it is prime and its reverse (12818447) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 74481821 - 2²⁶ = 7372957 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (74481829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37240910 + 37240911.

It is an arithmetic number, because the mean of its divisors is an integer number (37240911).

Almost surely, 2^74481821 is an apocalyptic number.

It is an amenable number.

74481821 is a deficient number, since it is larger than the sum of its proper divisors (1).

74481821 is an equidigital number, since it uses as much as digits as its factorization.

74481821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14336, while the sum is 35.

The square root of 74481821 is about 8630.2851053717. The cubic root of 74481821 is about 420.7428670770.

The spelling of 74481821 in words is "seventy-four million, four hundred eighty-one thousand, eight hundred twenty-one".