647764751 has 2 divisors, whose sum is σ = 647764752. Its totient is φ = 647764750.

The previous prime is 647764729. The next prime is 647764757. The reversal of 647764751 is 157467746.

647764751 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-647764751 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 647764696 and 647764705.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (647764757) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323882375 + 323882376.

It is an arithmetic number, because the mean of its divisors is an integer number (323882376).

Almost surely, 2^647764751 is an apocalyptic number.

647764751 is a deficient number, since it is larger than the sum of its proper divisors (1).

647764751 is an equidigital number, since it uses as much as digits as its factorization.

647764751 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 987840, while the sum is 47.

The square root of 647764751 is about 25451.2229765094. Note that the first 3 decimals coincide. The cubic root of 647764751 is about 865.2450110623.

The spelling of 647764751 in words is "six hundred forty-seven million, seven hundred sixty-four thousand, seven hundred fifty-one".