742247221 has 2 divisors, whose sum is σ = 742247222. Its totient is φ = 742247220.

The previous prime is 742247213. The next prime is 742247263. The reversal of 742247221 is 122742247.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 599564196 + 142683025 = 24486^2 + 11945^2 .

It is a cyclic number.

It is not a de Polignac number, because 742247221 - 2³ = 742247213 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 (742247281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 371123610 + 371123611.

It is an arithmetic number, because the mean of its divisors is an integer number (371123611).

Almost surely, 2^742247221 is an apocalyptic number.

It is an amenable number.

742247221 is a deficient number, since it is larger than the sum of its proper divisors (1).

742247221 is an equidigital number, since it uses as much as digits as its factorization.

742247221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12544, while the sum is 31.

The square root of 742247221 is about 27244.2144500443. The cubic root of 742247221 is about 905.4188393288.

Adding to 742247221 its reverse (122742247), we get a palindrome (864989468).

The spelling of 742247221 in words is "seven hundred forty-two million, two hundred forty-seven thousand, two hundred twenty-one".