7221144521 has 2 divisors, whose sum is σ = 7221144522. Its totient is φ = 7221144520.

The previous prime is 7221144487. The next prime is 7221144523. The reversal of 7221144521 is 1254411227.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5445702025 + 1775442496 = 73795^2 + 42136^2 .

It is a cyclic number.

It is not a de Polignac number, because 7221144521 - 2⁶ = 7221144457 is a prime.

Together with 7221144523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (7221144523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3610572260 + 3610572261.

It is an arithmetic number, because the mean of its divisors is an integer number (3610572261).

Almost surely, 2^7221144521 is an apocalyptic number.

It is an amenable number.

7221144521 is a deficient number, since it is larger than the sum of its proper divisors (1).

7221144521 is an equidigital number, since it uses as much as digits as its factorization.

7221144521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4480, while the sum is 29.

The square root of 7221144521 is about 84977.3176853683. The cubic root of 7221144521 is about 1932.8671820618.

Adding to 7221144521 its reverse (1254411227), we get a palindrome (8475555748).

The spelling of 7221144521 in words is "seven billion, two hundred twenty-one million, one hundred forty-four thousand, five hundred twenty-one".