1321787287 has 2 divisors, whose sum is σ = 1321787288. Its totient is φ = 1321787286.

The previous prime is 1321787267. The next prime is 1321787293. The reversal of 1321787287 is 7827871231.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1321787287 - 2¹⁵ = 1321754519 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321787267) 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, 660893643 + 660893644.

It is an arithmetic number, because the mean of its divisors is an integer number (660893644).

Almost surely, 2^1321787287 is an apocalyptic number.

1321787287 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321787287 is an equidigital number, since it uses as much as digits as its factorization.

1321787287 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 263424, while the sum is 46.

The square root of 1321787287 is about 36356.3926565879. The cubic root of 1321787287 is about 1097.4561843436.

The spelling of 1321787287 in words is "one billion, three hundred twenty-one million, seven hundred eighty-seven thousand, two hundred eighty-seven".