321523987 has 2 divisors, whose sum is σ = 321523988. Its totient is φ = 321523986.

The previous prime is 321523933. The next prime is 321523991. The reversal of 321523987 is 789325123.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 321523987 - 2⁷ = 321523859 is a prime.

It is not a weakly prime, because it can be changed into another prime (321520987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160761993 + 160761994.

It is an arithmetic number, because the mean of its divisors is an integer number (160761994).

Almost surely, 2^321523987 is an apocalyptic number.

321523987 is a deficient number, since it is larger than the sum of its proper divisors (1).

321523987 is an equidigital number, since it uses as much as digits as its factorization.

321523987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 40.

The square root of 321523987 is about 17931.0899557166. The cubic root of 321523987 is about 685.0744849475.

The spelling of 321523987 in words is "three hundred twenty-one million, five hundred twenty-three thousand, nine hundred eighty-seven".