623729 has 2 divisors, whose sum is σ = 623730. Its totient is φ = 623728.

The previous prime is 623723. The next prime is 623743. The reversal of 623729 is 927326.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 600625 + 23104 = 775^2 + 152^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-623729 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (623723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 311864 + 311865.

It is an arithmetic number, because the mean of its divisors is an integer number (311865).

2⁶²³⁷²⁹ is an apocalyptic number.

It is an amenable number.

623729 is a deficient number, since it is larger than the sum of its proper divisors (1).

623729 is an equidigital number, since it uses as much as digits as its factorization.

623729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4536, while the sum is 29.

The square root of 623729 is about 789.7651549670. The cubic root of 623729 is about 85.4408012177.

The spelling of 623729 in words is "six hundred twenty-three thousand, seven hundred twenty-nine".