1321314821 has 2 divisors, whose sum is σ = 1321314822. Its totient is φ = 1321314820.

The previous prime is 1321314811. The next prime is 1321314823. The reversal of 1321314821 is 1284131231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1318706596 + 2608225 = 36314^2 + 1615^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1321314821 is a prime.

Together with 1321314823, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321314823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660657410 + 660657411.

It is an arithmetic number, because the mean of its divisors is an integer number (660657411).

Almost surely, 2^1321314821 is an apocalyptic number.

It is an amenable number.

1321314821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321314821 is an equidigital number, since it uses as much as digits as its factorization.

1321314821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 26.

The square root of 1321314821 is about 36349.8943739868. The cubic root of 1321314821 is about 1097.3254087565.

The spelling of 1321314821 in words is "one billion, three hundred twenty-one million, three hundred fourteen thousand, eight hundred twenty-one".