156491 has 2 divisors, whose sum is σ = 156492. Its totient is φ = 156490.

The previous prime is 156487. The next prime is 156493. The reversal of 156491 is 194651.

156491 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 156491 - 2² = 156487 is a prime.

Together with 156493, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 156491.

It is not a weakly prime, because it can be changed into another prime (156493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78245 + 78246.

It is an arithmetic number, because the mean of its divisors is an integer number (78246).

2¹⁵⁶⁴⁹¹ is an apocalyptic number.

156491 is a deficient number, since it is larger than the sum of its proper divisors (1).

156491 is an equidigital number, since it uses as much as digits as its factorization.

156491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1080, while the sum is 26.

The square root of 156491 is about 395.5894336304. The cubic root of 156491 is about 53.8885446930. Note that the first 3 decimals are identical.

The spelling of 156491 in words is "one hundred fifty-six thousand, four hundred ninety-one".