678515623 has 2 divisors, whose sum is σ = 678515624. Its totient is φ = 678515622.

The previous prime is 678515609. The next prime is 678515681. The reversal of 678515623 is 326515876.

678515623 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 678515623 - 2²¹ = 676418471 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 678515623.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (678525623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339257811 + 339257812.

It is an arithmetic number, because the mean of its divisors is an integer number (339257812).

Almost surely, 2^678515623 is an apocalyptic number.

678515623 is a deficient number, since it is larger than the sum of its proper divisors (1).

678515623 is an equidigital number, since it uses as much as digits as its factorization.

678515623 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 302400, while the sum is 43.

The square root of 678515623 is about 26048.3324418282. The cubic root of 678515623 is about 878.7256101611.

The spelling of 678515623 in words is "six hundred seventy-eight million, five hundred fifteen thousand, six hundred twenty-three".