845531 has 2 divisors, whose sum is σ = 845532. Its totient is φ = 845530.

The previous prime is 845491. The next prime is 845567. The reversal of 845531 is 135548.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 845531 - 2¹⁰ = 844507 is a prime.

It is a super-2 number, since 2×845531² = 1429845343922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 845531.

It is not a weakly prime, because it can be changed into another prime (845231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 422765 + 422766.

It is an arithmetic number, because the mean of its divisors is an integer number (422766).

2⁸⁴⁵⁵³¹ is an apocalyptic number.

845531 is a deficient number, since it is larger than the sum of its proper divisors (1).

845531 is an equidigital number, since it uses as much as digits as its factorization.

845531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2400, while the sum is 26.

The square root of 845531 is about 919.5275961057. The cubic root of 845531 is about 94.5605185171.

The spelling of 845531 in words is "eight hundred forty-five thousand, five hundred thirty-one".