17859382921 has 2 divisors, whose sum is σ = 17859382922. Its totient is φ = 17859382920.

The previous prime is 17859382903. The next prime is 17859382969. The reversal of 17859382921 is 12928395871.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17763558400 + 95824521 = 133280^2 + 9789^2 .

It is a cyclic number.

It is not a de Polignac number, because 17859382921 - 2⁵ = 17859382889 is a prime.

It is not a weakly prime, because it can be changed into another prime (17859382991) 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, 8929691460 + 8929691461.

It is an arithmetic number, because the mean of its divisors is an integer number (8929691461).

Almost surely, 2^17859382921 is an apocalyptic number.

It is an amenable number.

17859382921 is a deficient number, since it is larger than the sum of its proper divisors (1).

17859382921 is an equidigital number, since it uses as much as digits as its factorization.

17859382921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2177280, while the sum is 55.

The spelling of 17859382921 in words is "seventeen billion, eight hundred fifty-nine million, three hundred eighty-two thousand, nine hundred twenty-one".