720731623 has 2 divisors, whose sum is σ = 720731624. Its totient is φ = 720731622.

The previous prime is 720731597. The next prime is 720731639. The reversal of 720731623 is 326137027.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 720731623 - 2⁵ = 720731591 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (720731023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360365811 + 360365812.

It is an arithmetic number, because the mean of its divisors is an integer number (360365812).

Almost surely, 2^720731623 is an apocalyptic number.

720731623 is a deficient number, since it is larger than the sum of its proper divisors (1).

720731623 is an equidigital number, since it uses as much as digits as its factorization.

720731623 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10584, while the sum is 31.

The square root of 720731623 is about 26846.4452581715. The cubic root of 720731623 is about 896.5844297623.

The spelling of 720731623 in words is "seven hundred twenty million, seven hundred thirty-one thousand, six hundred twenty-three".