978666879 has 8 divisors (see below), whose sum is σ = 1313201200. Its totient is φ = 648288576.

The previous prime is 978666851. The next prime is 978666881.

It is a happy number.

978666879 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 978666879 - 2⁷ = 978666751 is a prime.

It is a super-3 number, since 3×978666879³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (978666179) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1038454 + ... + 1039395.

It is an arithmetic number, because the mean of its divisors is an integer number (164150150).

Almost surely, 2^978666879 is an apocalyptic number.

978666879 is a deficient number, since it is larger than the sum of its proper divisors (334534321).

978666879 is a wasteful number, since it uses less digits than its factorization.

978666879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2078009.

The product of its digits is 54867456, while the sum is 66.

The square root of 978666879 is about 31283.6519447458. The cubic root of 978666879 is about 992.8377848077.

The spelling of 978666879 in words is "nine hundred seventy-eight million, six hundred sixty-six thousand, eight hundred seventy-nine".