678564493 has 2 divisors, whose sum is σ = 678564494. Its totient is φ = 678564492.

The previous prime is 678564463. The next prime is 678564527. The reversal of 678564493 is 394465876.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 432764809 + 245799684 = 20803^2 + 15678^2 .

It is a cyclic number.

It is not a de Polignac number, because 678564493 - 2¹⁷ = 678433421 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 678564493.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (678564433) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339282246 + 339282247.

It is an arithmetic number, because the mean of its divisors is an integer number (339282247).

Almost surely, 2^678564493 is an apocalyptic number.

It is an amenable number.

678564493 is a deficient number, since it is larger than the sum of its proper divisors (1).

678564493 is an equidigital number, since it uses as much as digits as its factorization.

678564493 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4354560, while the sum is 52.

The square root of 678564493 is about 26049.2704888256. The cubic root of 678564493 is about 878.7467063541.

The spelling of 678564493 in words is "six hundred seventy-eight million, five hundred sixty-four thousand, four hundred ninety-three".