978809659 has 2 divisors, whose sum is σ = 978809660. Its totient is φ = 978809658.

The previous prime is 978809647. The next prime is 978809759. The reversal of 978809659 is 956908879.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 978809659 - 2⁵ = 978809627 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 978809597 and 978809606.

It is not a weakly prime, because it can be changed into another prime (978809059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 489404829 + 489404830.

It is an arithmetic number, because the mean of its divisors is an integer number (489404830).

Almost surely, 2^978809659 is an apocalyptic number.

978809659 is a deficient number, since it is larger than the sum of its proper divisors (1).

978809659 is an equidigital number, since it uses as much as digits as its factorization.

978809659 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9797760, while the sum is 61.

The square root of 978809659 is about 31285.9338840956. The cubic root of 978809659 is about 992.8860649354.

The spelling of 978809659 in words is "nine hundred seventy-eight million, eight hundred nine thousand, six hundred fifty-nine".