678811257 has 12 divisors (see below), whose sum is σ = 980733780. Its totient is φ = 452435328.

The previous prime is 678811229. The next prime is 678811261. The reversal of 678811257 is 752118876.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 598242681 + 80568576 = 24459^2 + 8976^2 .

It is not a de Polignac number, because 678811257 - 2⁶ = 678811193 is a prime.

It is not an unprimeable number, because it can be changed into a prime (678811957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 61669 + ... + 71837.

It is an arithmetic number, because the mean of its divisors is an integer number (81727815).

Almost surely, 2^678811257 is an apocalyptic number.

It is an amenable number.

678811257 is a deficient number, since it is larger than the sum of its proper divisors (301922523).

678811257 is a wasteful number, since it uses less digits than its factorization.

678811257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17592 (or 17589 counting only the distinct ones).

The product of its digits is 188160, while the sum is 45.

The square root of 678811257 is about 26054.0065440999. The cubic root of 678811257 is about 878.8532139273.

The spelling of 678811257 in words is "six hundred seventy-eight million, eight hundred eleven thousand, two hundred fifty-seven".