678149 has 4 divisors (see below), whose sum is σ = 680940. Its totient is φ = 675360.

The previous prime is 678133. The next prime is 678157. The reversal of 678149 is 941876.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13924 + 664225 = 118^2 + 815^2 .

It is a cyclic number.

It is not a de Polignac number, because 678149 - 2⁴ = 678133 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 678149.

It is not an unprimeable number, because it can be changed into a prime (678169) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 992 + ... + 1529.

It is an arithmetic number, because the mean of its divisors is an integer number (170235).

2⁶⁷⁸¹⁴⁹ is an apocalyptic number.

It is an amenable number.

678149 is a deficient number, since it is larger than the sum of its proper divisors (2791).

678149 is a wasteful number, since it uses less digits than its factorization.

678149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2790.

The product of its digits is 12096, while the sum is 35.

The square root of 678149 is about 823.4980267129. The cubic root of 678149 is about 87.8567314095.

The spelling of 678149 in words is "six hundred seventy-eight thousand, one hundred forty-nine".