821985587 has 2 divisors, whose sum is σ = 821985588. Its totient is φ = 821985586.

The previous prime is 821985559. The next prime is 821985601. The reversal of 821985587 is 785589128.

821985587 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 821985587 - 2⁸ = 821985331 is a prime.

It is not a weakly prime, because it can be changed into another prime (821985517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410992793 + 410992794.

It is an arithmetic number, because the mean of its divisors is an integer number (410992794).

Almost surely, 2^821985587 is an apocalyptic number.

821985587 is a deficient number, since it is larger than the sum of its proper divisors (1).

821985587 is an equidigital number, since it uses as much as digits as its factorization.

821985587 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1612800, while the sum is 53.

The square root of 821985587 is about 28670.2910170092. The cubic root of 821985587 is about 936.7450370436.

The spelling of 821985587 in words is "eight hundred twenty-one million, nine hundred eighty-five thousand, five hundred eighty-seven".