647977507 has 2 divisors, whose sum is σ = 647977508. Its totient is φ = 647977506.

The previous prime is 647977439. The next prime is 647977529. The reversal of 647977507 is 705779746.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-647977507 is a prime.

It is not a weakly prime, because it can be changed into another prime (647977207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323988753 + 323988754.

It is an arithmetic number, because the mean of its divisors is an integer number (323988754).

Almost surely, 2^647977507 is an apocalyptic number.

647977507 is a deficient number, since it is larger than the sum of its proper divisors (1).

647977507 is an equidigital number, since it uses as much as digits as its factorization.

647977507 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2593080, while the sum is 52.

The square root of 647977507 is about 25455.4023146365. The cubic root of 647977507 is about 865.3397295625.

The spelling of 647977507 in words is "six hundred forty-seven million, nine hundred seventy-seven thousand, five hundred seven".