158491 has 4 divisors (see below), whose sum is σ = 167832. Its totient is φ = 149152.

The previous prime is 158489. The next prime is 158507. The reversal of 158491 is 194851.

It is a happy number.

158491 is nontrivially palindromic in base 12.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 194851 = 29 ⋅6719.

It is a cyclic number.

It is not a de Polignac number, because 158491 - 2¹ = 158489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (158591) 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, 4645 + ... + 4678.

It is an arithmetic number, because the mean of its divisors is an integer number (41958).

2¹⁵⁸⁴⁹¹ is an apocalyptic number.

158491 is a deficient number, since it is larger than the sum of its proper divisors (9341).

158491 is an equidigital number, since it uses as much as digits as its factorization.

158491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9340.

The product of its digits is 1440, while the sum is 28.

The square root of 158491 is about 398.1092814793. The cubic root of 158491 is about 54.1171439545.

The spelling of 158491 in words is "one hundred fifty-eight thousand, four hundred ninety-one".