8159978 has 4 divisors (see below), whose sum is σ = 12239970. Its totient is φ = 4079988.

The previous prime is 8159971. The next prime is 8159993. The reversal of 8159978 is 8799518.

It is a happy number.

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., 7912969 + 247009 = 2813^2 + 497^2 .

It is not an unprimeable number, because it can be changed into a prime (8159971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2039993 + ... + 2039996.

Almost surely, 2^8159978 is an apocalyptic number.

8159978 is a deficient number, since it is larger than the sum of its proper divisors (4079992).

8159978 is a wasteful number, since it uses less digits than its factorization.

8159978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4079991.

The product of its digits is 181440, while the sum is 47.

The square root of 8159978 is about 2856.5675206443. The cubic root of 8159978 is about 201.3243609829.

The spelling of 8159978 in words is "eight million, one hundred fifty-nine thousand, nine hundred seventy-eight".