75222021221 has 2 divisors, whose sum is σ = 75222021222. Its totient is φ = 75222021220.

The previous prime is 75222021197. The next prime is 75222021241. The reversal of 75222021221 is 12212022257.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49958508196 + 25263513025 = 223514^2 + 158945^2 .

It is an emirp because it is prime and its reverse (12212022257) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 75222021221 - 2¹⁰ = 75222020197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (75222021241) 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, 37611010610 + 37611010611.

It is an arithmetic number, because the mean of its divisors is an integer number (37611010611).

Almost surely, 2^75222021221 is an apocalyptic number.

It is an amenable number.

75222021221 is a deficient number, since it is larger than the sum of its proper divisors (1).

75222021221 is an equidigital number, since it uses as much as digits as its factorization.

75222021221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2240, while the sum is 26.

Adding to 75222021221 its reverse (12212022257), we get a palindrome (87434043478).

The spelling of 75222021221 in words is "seventy-five billion, two hundred twenty-two million, twenty-one thousand, two hundred twenty-one".