660726757 has 2 divisors, whose sum is σ = 660726758. Its totient is φ = 660726756.

The previous prime is 660726719. The next prime is 660726761. The reversal of 660726757 is 757627066.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 423289476 + 237437281 = 20574^2 + 15409^2 .

It is a cyclic number.

It is not a de Polignac number, because 660726757 - 2⁷ = 660726629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (660726257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330363378 + 330363379.

It is an arithmetic number, because the mean of its divisors is an integer number (330363379).

Almost surely, 2^660726757 is an apocalyptic number.

It is an amenable number.

660726757 is a deficient number, since it is larger than the sum of its proper divisors (1).

660726757 is an equidigital number, since it uses as much as digits as its factorization.

660726757 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 740880, while the sum is 46.

The square root of 660726757 is about 25704.6057546114. The cubic root of 660726757 is about 870.9782263113.

The spelling of 660726757 in words is "six hundred sixty million, seven hundred twenty-six thousand, seven hundred fifty-seven".