623591 has 2 divisors, whose sum is σ = 623592. Its totient is φ = 623590.

The previous prime is 623563. The next prime is 623617. The reversal of 623591 is 195326.

It is an a-pointer prime, because the next prime (623617) can be obtained adding 623591 to its sum of digits (26).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 623591 - 2¹⁸ = 361447 is a prime.

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 623591.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (623521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 311795 + 311796.

It is an arithmetic number, because the mean of its divisors is an integer number (311796).

2⁶²³⁵⁹¹ is an apocalyptic number.

623591 is a deficient number, since it is larger than the sum of its proper divisors (1).

623591 is an equidigital number, since it uses as much as digits as its factorization.

623591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1620, while the sum is 26.

The square root of 623591 is about 789.6777823898. The cubic root of 623591 is about 85.4344994957.

The spelling of 623591 in words is "six hundred twenty-three thousand, five hundred ninety-one".