623869 has 2 divisors, whose sum is σ = 623870. Its totient is φ = 623868.

The previous prime is 623867. The next prime is 623879. The reversal of 623869 is 968326.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 315844 + 308025 = 562^2 + 555^2 .

It is a cyclic number.

It is not a de Polignac number, because 623869 - 2¹ = 623867 is a prime.

It is a super-2 number, since 2×623869² = 778425058322, which contains 22 as substring.

Together with 623867, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (623867) 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, 311934 + 311935.

It is an arithmetic number, because the mean of its divisors is an integer number (311935).

2⁶²³⁸⁶⁹ is an apocalyptic number.

It is an amenable number.

623869 is a deficient number, since it is larger than the sum of its proper divisors (1).

623869 is an equidigital number, since it uses as much as digits as its factorization.

623869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 34.

The square root of 623869 is about 789.8537839373. The cubic root of 623869 is about 85.4471933192.

The spelling of 623869 in words is "six hundred twenty-three thousand, eight hundred sixty-nine".