1321085819 has 2 divisors, whose sum is σ = 1321085820. Its totient is φ = 1321085818.

The previous prime is 1321085803. The next prime is 1321085849. The reversal of 1321085819 is 9185801231.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1321085819 - 2⁴ = 1321085803 is a prime.

It is a super-2 number, since 2×1321085819² = 3490535482325801522, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1321085849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660542909 + 660542910.

It is an arithmetic number, because the mean of its divisors is an integer number (660542910).

Almost surely, 2^1321085819 is an apocalyptic number.

1321085819 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321085819 is an equidigital number, since it uses as much as digits as its factorization.

1321085819 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 38.

The square root of 1321085819 is about 36346.7442696041. The cubic root of 1321085819 is about 1097.2620112406.

The spelling of 1321085819 in words is "one billion, three hundred twenty-one million, eighty-five thousand, eight hundred nineteen".