978194785 has 16 divisors (see below), whose sum is σ = 1206210816. Its totient is φ = 761177088.

The previous prime is 978194747. The next prime is 978194821. The reversal of 978194785 is 587491879.

It is a 5-Lehmer number, since φ(978194785) divides (978194785-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 978194785 - 2¹³ = 978186593 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25537 + ... + 51073.

It is an arithmetic number, because the mean of its divisors is an integer number (75388176).

Almost surely, 2^978194785 is an apocalyptic number.

978194785 is the 25537-th pentagonal number.

It is an amenable number.

978194785 is a deficient number, since it is larger than the sum of its proper divisors (228016031).

978194785 is a wasteful number, since it uses less digits than its factorization.

978194785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25752.

The product of its digits is 5080320, while the sum is 58.

The square root of 978194785 is about 31276.1056559157. The cubic root of 978194785 is about 992.6781158546.

The spelling of 978194785 in words is "nine hundred seventy-eight million, one hundred ninety-four thousand, seven hundred eighty-five".