155851 has 2 divisors, whose sum is σ = 155852. Its totient is φ = 155850.

The previous prime is 155849. The next prime is 155861. The reversal of 155851 is 158551.

It is a weak prime.

It is an emirp because it is prime and its reverse (158551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 155851 - 2¹ = 155849 is a prime.

Together with 155849, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (155801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77925 + 77926.

It is an arithmetic number, because the mean of its divisors is an integer number (77926).

2¹⁵⁵⁸⁵¹ is an apocalyptic number.

155851 is a deficient number, since it is larger than the sum of its proper divisors (1).

155851 is an equidigital number, since it uses as much as digits as its factorization.

155851 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1000, while the sum is 25.

The square root of 155851 is about 394.7796853943. The cubic root of 155851 is about 53.8149818007.

The spelling of 155851 in words is "one hundred fifty-five thousand, eight hundred fifty-one".