158678993 has 4 divisors (see below), whose sum is σ = 173104368. Its totient is φ = 144253620.

The previous prime is 158678959. The next prime is 158679011. The reversal of 158678993 is 399876851.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 399876851 = 11 ⋅36352441.

It is a cyclic number.

It is not a de Polignac number, because 158678993 - 2²² = 154484689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (158678953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7212671 + ... + 7212692.

It is an arithmetic number, because the mean of its divisors is an integer number (43276092).

Almost surely, 2^158678993 is an apocalyptic number.

It is an amenable number.

158678993 is a deficient number, since it is larger than the sum of its proper divisors (14425375).

158678993 is a wasteful number, since it uses less digits than its factorization.

158678993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14425374.

The product of its digits is 3265920, while the sum is 56.

The square root of 158678993 is about 12596.7850263470. The cubic root of 158678993 is about 541.3853239177.

The spelling of 158678993 in words is "one hundred fifty-eight million, six hundred seventy-eight thousand, nine hundred ninety-three".