158188993 has 4 divisors (see below), whose sum is σ = 158261040. Its totient is φ = 158116948.

The previous prime is 158188991. The next prime is 158188999. The reversal of 158188993 is 399881851.

158188993 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, 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: 399881851 = 2137 ⋅187123.

It is a cyclic number.

It is not a de Polignac number, because 158188993 - 2¹ = 158188991 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 158188993.

It is not an unprimeable number, because it can be changed into a prime (158188991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32623 + ... + 37156.

It is an arithmetic number, because the mean of its divisors is an integer number (39565260).

Almost surely, 2^158188993 is an apocalyptic number.

It is an amenable number.

158188993 is a deficient number, since it is larger than the sum of its proper divisors (72047).

158188993 is an equidigital number, since it uses as much as digits as its factorization.

158188993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72046.

The product of its digits is 622080, while the sum is 52.

The square root of 158188993 is about 12577.3205811095. The cubic root of 158188993 is about 540.8274841914.

The spelling of 158188993 in words is "one hundred fifty-eight million, one hundred eighty-eight thousand, nine hundred ninety-three".