1321890887 has 2 divisors, whose sum is σ = 1321890888. Its totient is φ = 1321890886.

The previous prime is 1321890841. The next prime is 1321890919. The reversal of 1321890887 is 7880981231.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1321890887 - 2⁸ = 1321890631 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321890587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660945443 + 660945444.

It is an arithmetic number, because the mean of its divisors is an integer number (660945444).

Almost surely, 2^1321890887 is an apocalyptic number.

1321890887 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321890887 is an equidigital number, since it uses as much as digits as its factorization.

1321890887 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 193536, while the sum is 47.

The square root of 1321890887 is about 36357.8174124905. The cubic root of 1321890887 is about 1097.4848559994.

The spelling of 1321890887 in words is "one billion, three hundred twenty-one million, eight hundred ninety thousand, eight hundred eighty-seven".