77349221 has 2 divisors, whose sum is σ = 77349222. Its totient is φ = 77349220.

The previous prime is 77349211. The next prime is 77349227. The reversal of 77349221 is 12294377.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71656225 + 5692996 = 8465^2 + 2386^2 .

It is a cyclic number.

It is not a de Polignac number, because 77349221 - 2¹⁸ = 77087077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77349227) 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, 38674610 + 38674611.

It is an arithmetic number, because the mean of its divisors is an integer number (38674611).

Almost surely, 2^77349221 is an apocalyptic number.

It is an amenable number.

77349221 is a deficient number, since it is larger than the sum of its proper divisors (1).

77349221 is an equidigital number, since it uses as much as digits as its factorization.

77349221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21168, while the sum is 35.

The square root of 77349221 is about 8794.8405898004. The cubic root of 77349221 is about 426.0742760272.

It can be divided in two parts, 773 and 49221, that added together give a palindrome (49994).

The spelling of 77349221 in words is "seventy-seven million, three hundred forty-nine thousand, two hundred twenty-one".