978228891 has 6 divisors (see below), whose sum is σ = 1412997300. Its totient is φ = 652152588.

The previous prime is 978228883. The next prime is 978228929. The reversal of 978228891 is 198822879.

It is not a de Polignac number, because 978228891 - 2³ = 978228883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (978228821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 54346041 + ... + 54346058.

It is an arithmetic number, because the mean of its divisors is an integer number (235499550).

Almost surely, 2^978228891 is an apocalyptic number.

978228891 is a deficient number, since it is larger than the sum of its proper divisors (434768409).

978228891 is a wasteful number, since it uses less digits than its factorization.

978228891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108692105 (or 108692102 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 54.

The square root of 978228891 is about 31276.6508916796. The cubic root of 978228891 is about 992.6896527137.

The spelling of 978228891 in words is "nine hundred seventy-eight million, two hundred twenty-eight thousand, eight hundred ninety-one".