820616578 has 8 divisors (see below), whose sum is σ = 1231400268. Its totient is φ = 410149824.

The previous prime is 820616561. The next prime is 820616581. The reversal of 820616578 is 875616028.

It can be written as a sum of positive squares in 2 ways, for example, as 719473329 + 101143249 = 26823^2 + 10057^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72651 + ... + 83182.

Almost surely, 2^820616578 is an apocalyptic number.

820616578 is a deficient number, since it is larger than the sum of its proper divisors (410783690).

820616578 is a wasteful number, since it uses less digits than its factorization.

820616578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158468.

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 820616578 is about 28646.4060223966. The cubic root of 820616578 is about 936.2247014827.

The spelling of 820616578 in words is "eight hundred twenty million, six hundred sixteen thousand, five hundred seventy-eight".