864820987 has 2 divisors, whose sum is σ = 864820988. Its totient is φ = 864820986.

The previous prime is 864820939. The next prime is 864821003. The reversal of 864820987 is 789028468.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 864820987 - 2²⁷ = 730603259 is a prime.

It is not a weakly prime, because it can be changed into another prime (864820937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432410493 + 432410494.

It is an arithmetic number, because the mean of its divisors is an integer number (432410494).

Almost surely, 2^864820987 is an apocalyptic number.

864820987 is a deficient number, since it is larger than the sum of its proper divisors (1).

864820987 is an equidigital number, since it uses as much as digits as its factorization.

864820987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1548288, while the sum is 52.

The square root of 864820987 is about 29407.8388699340. The cubic root of 864820987 is about 952.7422105929.

The spelling of 864820987 in words is "eight hundred sixty-four million, eight hundred twenty thousand, nine hundred eighty-seven".