660560749 has 2 divisors, whose sum is σ = 660560750. Its totient is φ = 660560748.

The previous prime is 660560743. The next prime is 660560807. The reversal of 660560749 is 947065066.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 473062500 + 187498249 = 21750^2 + 13693^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-660560749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (660560743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330280374 + 330280375.

It is an arithmetic number, because the mean of its divisors is an integer number (330280375).

Almost surely, 2^660560749 is an apocalyptic number.

It is an amenable number.

660560749 is a deficient number, since it is larger than the sum of its proper divisors (1).

660560749 is an equidigital number, since it uses as much as digits as its factorization.

660560749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 272160, while the sum is 43.

The square root of 660560749 is about 25701.3764028310. The cubic root of 660560749 is about 870.9052755981.

The spelling of 660560749 in words is "six hundred sixty million, five hundred sixty thousand, seven hundred forty-nine".