859964821 has 2 divisors, whose sum is σ = 859964822. Its totient is φ = 859964820.

The previous prime is 859964801. The next prime is 859964887. The reversal of 859964821 is 128469958.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 687173796 + 172791025 = 26214^2 + 13145^2 .

It is a cyclic number.

It is not a de Polignac number, because 859964821 - 2¹⁵ = 859932053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (859964801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 429982410 + 429982411.

It is an arithmetic number, because the mean of its divisors is an integer number (429982411).

Almost surely, 2^859964821 is an apocalyptic number.

It is an amenable number.

859964821 is a deficient number, since it is larger than the sum of its proper divisors (1).

859964821 is an equidigital number, since it uses as much as digits as its factorization.

859964821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1244160, while the sum is 52.

The square root of 859964821 is about 29325.1567941247. The cubic root of 859964821 is about 950.9555744149.

The spelling of 859964821 in words is "eight hundred fifty-nine million, nine hundred sixty-four thousand, eight hundred twenty-one".