859984921 has 2 divisors, whose sum is σ = 859984922. Its totient is φ = 859984920.

The previous prime is 859984913. The next prime is 859985023. The reversal of 859984921 is 129489958.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 684554896 + 175430025 = 26164^2 + 13245^2 .

It is a cyclic number.

It is not a de Polignac number, because 859984921 - 2³ = 859984913 is a prime.

It is not a weakly prime, because it can be changed into another prime (859984121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 429992460 + 429992461.

It is an arithmetic number, because the mean of its divisors is an integer number (429992461).

Almost surely, 2^859984921 is an apocalyptic number.

It is an amenable number.

859984921 is a deficient number, since it is larger than the sum of its proper divisors (1).

859984921 is an equidigital number, since it uses as much as digits as its factorization.

859984921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1866240, while the sum is 55.

The square root of 859984921 is about 29325.4995012873. The cubic root of 859984921 is about 950.9629832677.

The spelling of 859984921 in words is "eight hundred fifty-nine million, nine hundred eighty-four thousand, nine hundred twenty-one".