155858 has 4 divisors (see below), whose sum is σ = 233790. Its totient is φ = 77928.

The previous prime is 155851. The next prime is 155861. The reversal of 155858 is 858551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 858551 = 17 ⋅50503.

It can be written as a sum of positive squares in only one way, i.e., 104329 + 51529 = 323^2 + 227^2 .

It is not an unprimeable number, because it can be changed into a prime (155851) by changing a digit.

155858 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38963 + ... + 38966.

2¹⁵⁵⁸⁵⁸ is an apocalyptic number.

155858 is a deficient number, since it is larger than the sum of its proper divisors (77932).

155858 is an equidigital number, since it uses as much as digits as its factorization.

155858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77931.

The product of its digits is 8000, while the sum is 32.

The square root of 155858 is about 394.7885509991. The cubic root of 155858 is about 53.8157874831.

The spelling of 155858 in words is "one hundred fifty-five thousand, eight hundred fifty-eight".