1221310247 has 2 divisors, whose sum is σ = 1221310248. Its totient is φ = 1221310246.

The previous prime is 1221310241. The next prime is 1221310261. The reversal of 1221310247 is 7420131221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221310247 - 2⁶ = 1221310183 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221310241) 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, 610655123 + 610655124.

It is an arithmetic number, because the mean of its divisors is an integer number (610655124).

Almost surely, 2^1221310247 is an apocalyptic number.

1221310247 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221310247 is an equidigital number, since it uses as much as digits as its factorization.

1221310247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 1221310247 is about 34947.2494911974. The cubic root of 1221310247 is about 1068.9121172995.

Adding to 1221310247 its reverse (7420131221), we get a palindrome (8641441468).

The spelling of 1221310247 in words is "one billion, two hundred twenty-one million, three hundred ten thousand, two hundred forty-seven".