719643689 has 2 divisors, whose sum is σ = 719643690. Its totient is φ = 719643688.

The previous prime is 719643667. The next prime is 719643697. The reversal of 719643689 is 986346917.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 662187289 + 57456400 = 25733^2 + 7580^2 .

It is an emirp because it is prime and its reverse (986346917) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-719643689 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 719643689.

It is not a weakly prime, because it can be changed into another prime (719643629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 359821844 + 359821845.

It is an arithmetic number, because the mean of its divisors is an integer number (359821845).

Almost surely, 2^719643689 is an apocalyptic number.

It is an amenable number.

719643689 is a deficient number, since it is larger than the sum of its proper divisors (1).

719643689 is an equidigital number, since it uses as much as digits as its factorization.

719643689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1959552, while the sum is 53.

The square root of 719643689 is about 26826.1754448896. The cubic root of 719643689 is about 896.1330754891.

The spelling of 719643689 in words is "seven hundred nineteen million, six hundred forty-three thousand, six hundred eighty-nine".