389978 has 4 divisors (see below), whose sum is σ = 584970. Its totient is φ = 194988.

The previous prime is 389971. The next prime is 389981. The reversal of 389978 is 879983.

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

It can be written as a sum of positive squares in only one way, i.e., 388129 + 1849 = 623^2 + 43^2 .

It is not an unprimeable number, because it can be changed into a prime (389971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97493 + ... + 97496.

2³⁸⁹⁹⁷⁸ is an apocalyptic number.

389978 is a deficient number, since it is larger than the sum of its proper divisors (194992).

389978 is a wasteful number, since it uses less digits than its factorization.

389978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194991.

The product of its digits is 108864, while the sum is 44.

The square root of 389978 is about 624.4821854945. The cubic root of 389978 is about 73.0600619100.

The spelling of 389978 in words is "three hundred eighty-nine thousand, nine hundred seventy-eight".