647046761 has 2 divisors, whose sum is σ = 647046762. Its totient is φ = 647046760.

The previous prime is 647046749. The next prime is 647046823. The reversal of 647046761 is 167640746.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 382789225 + 264257536 = 19565^2 + 16256^2 .

It is a cyclic number.

It is not a de Polignac number, because 647046761 - 2¹⁸ = 646784617 is a prime.

It is a super-2 number, since 2×647046761² = 837339021841182242, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (647046661) 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, 323523380 + 323523381.

It is an arithmetic number, because the mean of its divisors is an integer number (323523381).

Almost surely, 2^647046761 is an apocalyptic number.

It is an amenable number.

647046761 is a deficient number, since it is larger than the sum of its proper divisors (1).

647046761 is an equidigital number, since it uses as much as digits as its factorization.

647046761 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 169344, while the sum is 41.

The square root of 647046761 is about 25437.1138496489. The cubic root of 647046761 is about 864.9252103246.

The spelling of 647046761 in words is "six hundred forty-seven million, forty-six thousand, seven hundred sixty-one".