1321412581 has 2 divisors, whose sum is σ = 1321412582. Its totient is φ = 1321412580.

The previous prime is 1321412467. The next prime is 1321412663. The reversal of 1321412581 is 1852141231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 711075556 + 610337025 = 26666^2 + 24705^2 .

It is a cyclic number.

It is not a de Polignac number, because 1321412581 - 2¹⁷ = 1321281509 is a prime.

It is a super-2 number, since 2×1321412581² = 3492262418450163122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321410581) 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, 660706290 + 660706291.

It is an arithmetic number, because the mean of its divisors is an integer number (660706291).

Almost surely, 2^1321412581 is an apocalyptic number.

It is an amenable number.

1321412581 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321412581 is an equidigital number, since it uses as much as digits as its factorization.

1321412581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1920, while the sum is 28.

The square root of 1321412581 is about 36351.2390572866. The cubic root of 1321412581 is about 1097.3524706610.

The spelling of 1321412581 in words is "one billion, three hundred twenty-one million, four hundred twelve thousand, five hundred eighty-one".