979978 has 4 divisors (see below), whose sum is σ = 1469970. Its totient is φ = 489988.

The previous prime is 979969. The next prime is 979987. The reversal of 979978 is 879979.

979978 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is an interprime number because it is at equal distance from previous prime (979969) and next prime (979987).

It can be written as a sum of positive squares in only one way, i.e., 966289 + 13689 = 983^2 + 117^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a plaindrome in base 15.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 244993 + ... + 244996.

2⁹⁷⁹⁹⁷⁸ is an apocalyptic number.

979978 is a deficient number, since it is larger than the sum of its proper divisors (489992).

979978 is a wasteful number, since it uses less digits than its factorization.

979978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 489991.

The product of its digits is 285768, while the sum is 49.

The square root of 979978 is about 989.9383819208. The cubic root of 979978 is about 99.3280955553.

Subtracting from 979978 its reverse (879979), we obtain a palindrome (99999).

The spelling of 979978 in words is "nine hundred seventy-nine thousand, nine hundred seventy-eight".