1321971247 has 2 divisors, whose sum is σ = 1321971248. Its totient is φ = 1321971246.

The previous prime is 1321971229. The next prime is 1321971257. The reversal of 1321971247 is 7421791231.

It is a strong prime.

It is an emirp because it is prime and its reverse (7421791231) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1321971247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321971257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660985623 + 660985624.

It is an arithmetic number, because the mean of its divisors is an integer number (660985624).

Almost surely, 2^1321971247 is an apocalyptic number.

1321971247 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321971247 is an equidigital number, since it uses as much as digits as its factorization.

1321971247 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21168, while the sum is 37.

The square root of 1321971247 is about 36358.9225225391. The cubic root of 1321971247 is about 1097.5070948737.

The spelling of 1321971247 in words is "one billion, three hundred twenty-one million, nine hundred seventy-one thousand, two hundred forty-seven".