617198978 has 18 divisors (see below), whose sum is σ = 1018250793. Its totient is φ = 280369320.

The previous prime is 617198929. The next prime is 617198993. The reversal of 617198978 is 879891716.

It can be written as a sum of positive squares in 2 ways, for example, as 555686329 + 61512649 = 23573^2 + 7843^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=17567.

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 8 ways as a sum of consecutive naturals, for example, 385676 + ... + 387272.

Almost surely, 2^617198978 is an apocalyptic number.

617198978 is a deficient number, since it is larger than the sum of its proper divisors (401051815).

617198978 is an equidigital number, since it uses as much as digits as its factorization.

617198978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3218 (or 1610 counting only the distinct ones).

The product of its digits is 1524096, while the sum is 56.

The square root of 617198978 is about 24843.4896502082. The cubic root of 617198978 is about 851.4158538980.

The spelling of 617198978 in words is "six hundred seventeen million, one hundred ninety-eight thousand, nine hundred seventy-eight".