678603217 has 2 divisors, whose sum is σ = 678603218. Its totient is φ = 678603216.

The previous prime is 678603203. The next prime is 678603227. The reversal of 678603217 is 712306876.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 664041361 + 14561856 = 25769^2 + 3816^2 .

It is a cyclic number.

It is not a de Polignac number, because 678603217 - 2⁷ = 678603089 is a prime.

It is a super-2 number, since 2×678603217² = 921004652245498178, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 678603217.

It is not a weakly prime, because it can be changed into another prime (678603227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339301608 + 339301609.

It is an arithmetic number, because the mean of its divisors is an integer number (339301609).

Almost surely, 2^678603217 is an apocalyptic number.

It is an amenable number.

678603217 is a deficient number, since it is larger than the sum of its proper divisors (1).

678603217 is an equidigital number, since it uses as much as digits as its factorization.

678603217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 84672, while the sum is 40.

The square root of 678603217 is about 26050.0137619925. The cubic root of 678603217 is about 878.7634220044.

The spelling of 678603217 in words is "six hundred seventy-eight million, six hundred three thousand, two hundred seventeen".