726664777 has 2 divisors, whose sum is σ = 726664778. Its totient is φ = 726664776.

The previous prime is 726664759. The next prime is 726664819. The reversal of 726664777 is 777466627.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 535644736 + 191020041 = 23144^2 + 13821^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-726664777 is a prime.

It is not a weakly prime, because it can be changed into another prime (726664877) 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, 363332388 + 363332389.

It is an arithmetic number, because the mean of its divisors is an integer number (363332389).

Almost surely, 2^726664777 is an apocalyptic number.

It is an amenable number.

726664777 is a deficient number, since it is larger than the sum of its proper divisors (1).

726664777 is an equidigital number, since it uses as much as digits as its factorization.

726664777 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4148928, while the sum is 52.

The square root of 726664777 is about 26956.7204422200. The cubic root of 726664777 is about 899.0379749223.

The spelling of 726664777 in words is "seven hundred twenty-six million, six hundred sixty-four thousand, seven hundred seventy-seven".