774828221 has 2 divisors, whose sum is σ = 774828222. Its totient is φ = 774828220.

The previous prime is 774828217. The next prime is 774828281. The reversal of 774828221 is 122828477.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 762367321 + 12460900 = 27611^2 + 3530^2 .

It is an emirp because it is prime and its reverse (122828477) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 774828221 - 2² = 774828217 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (774828281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 387414110 + 387414111.

It is an arithmetic number, because the mean of its divisors is an integer number (387414111).

Almost surely, 2^774828221 is an apocalyptic number.

It is an amenable number.

774828221 is a deficient number, since it is larger than the sum of its proper divisors (1).

774828221 is an equidigital number, since it uses as much as digits as its factorization.

774828221 is an evil number, because the sum of its binary digits is even.

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

The square root of 774828221 is about 27835.7364012523. The cubic root of 774828221 is about 918.4774047069.

The spelling of 774828221 in words is "seven hundred seventy-four million, eight hundred twenty-eight thousand, two hundred twenty-one".