647579761 has 2 divisors, whose sum is σ = 647579762. Its totient is φ = 647579760.

The previous prime is 647579747. The next prime is 647579813. The reversal of 647579761 is 167975746.

It is an a-pointer prime, because the next prime (647579813) can be obtained adding 647579761 to its sum of digits (52).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 619064161 + 28515600 = 24881^2 + 5340^2 .

It is a cyclic number.

It is not a de Polignac number, because 647579761 - 2²³ = 639191153 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 647579699 and 647579708.

It is not a weakly prime, because it can be changed into another prime (647079761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323789880 + 323789881.

It is an arithmetic number, because the mean of its divisors is an integer number (323789881).

Almost surely, 2^647579761 is an apocalyptic number.

It is an amenable number.

647579761 is a deficient number, since it is larger than the sum of its proper divisors (1).

647579761 is an equidigital number, since it uses as much as digits as its factorization.

647579761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2222640, while the sum is 52.

The square root of 647579761 is about 25447.5885105053. The cubic root of 647579761 is about 865.1626370659.

The spelling of 647579761 in words is "six hundred forty-seven million, five hundred seventy-nine thousand, seven hundred sixty-one".