1320021397 has 2 divisors, whose sum is σ = 1320021398. Its totient is φ = 1320021396.

The previous prime is 1320021343. The next prime is 1320021401. The reversal of 1320021397 is 7931200231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 787981041 + 532040356 = 28071^2 + 23066^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1320021397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1320021097) 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, 660010698 + 660010699.

It is an arithmetic number, because the mean of its divisors is an integer number (660010699).

Almost surely, 2^1320021397 is an apocalyptic number.

It is an amenable number.

1320021397 is a deficient number, since it is larger than the sum of its proper divisors (1).

1320021397 is an equidigital number, since it uses as much as digits as its factorization.

1320021397 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2268, while the sum is 28.

The square root of 1320021397 is about 36332.0987144976. The cubic root of 1320021397 is about 1096.9672376467.

The spelling of 1320021397 in words is "one billion, three hundred twenty million, twenty-one thousand, three hundred ninety-seven".