159778 has 4 divisors (see below), whose sum is σ = 239670. Its totient is φ = 79888.

The previous prime is 159773. The next prime is 159779. The reversal of 159778 is 877951.

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., 154449 + 5329 = 393^2 + 73^2 .

It is not an unprimeable number, because it can be changed into a prime (159773) by changing a digit.

159778 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39943 + ... + 39946.

2¹⁵⁹⁷⁷⁸ is an apocalyptic number.

159778 is a deficient number, since it is larger than the sum of its proper divisors (79892).

159778 is an equidigital number, since it uses as much as digits as its factorization.

159778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79891.

The product of its digits is 17640, while the sum is 37.

The square root of 159778 is about 399.7224036754. The cubic root of 159778 is about 54.2632323474.

The spelling of 159778 in words is "one hundred fifty-nine thousand, seven hundred seventy-eight".