845491 has 2 divisors, whose sum is σ = 845492. Its totient is φ = 845490.

The previous prime is 845489. The next prime is 845531. The reversal of 845491 is 194548.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 845491 - 2¹ = 845489 is a prime.

Together with 845489, it forms a pair of twin primes.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (845431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 422745 + 422746.

It is an arithmetic number, because the mean of its divisors is an integer number (422746).

2⁸⁴⁵⁴⁹¹ is an apocalyptic number.

845491 is a deficient number, since it is larger than the sum of its proper divisors (1).

845491 is an equidigital number, since it uses as much as digits as its factorization.

845491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5760, while the sum is 31.

The square root of 845491 is about 919.5058455497. The cubic root of 845491 is about 94.5590273514.

The spelling of 845491 in words is "eight hundred forty-five thousand, four hundred ninety-one".