671744729 has 2 divisors, whose sum is σ = 671744730. Its totient is φ = 671744728.

The previous prime is 671744701. The next prime is 671744741. The reversal of 671744729 is 927447176.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 503912704 + 167832025 = 22448^2 + 12955^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-671744729 is a prime.

It is not a weakly prime, because it can be changed into another prime (671744329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335872364 + 335872365.

It is an arithmetic number, because the mean of its divisors is an integer number (335872365).

Almost surely, 2^671744729 is an apocalyptic number.

It is an amenable number.

671744729 is a deficient number, since it is larger than the sum of its proper divisors (1).

671744729 is an equidigital number, since it uses as much as digits as its factorization.

671744729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 592704, while the sum is 47.

The square root of 671744729 is about 25918.0386796532. The cubic root of 671744729 is about 875.7929047812.

The spelling of 671744729 in words is "six hundred seventy-one million, seven hundred forty-four thousand, seven hundred twenty-nine".