647966587 has 2 divisors, whose sum is σ = 647966588. Its totient is φ = 647966586.

The previous prime is 647966569. The next prime is 647966617. The reversal of 647966587 is 785669746.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-647966587 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (647966507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323983293 + 323983294.

It is an arithmetic number, because the mean of its divisors is an integer number (323983294).

Almost surely, 2^647966587 is an apocalyptic number.

647966587 is a deficient number, since it is larger than the sum of its proper divisors (1).

647966587 is an equidigital number, since it uses as much as digits as its factorization.

647966587 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15240960, while the sum is 58.

The square root of 647966587 is about 25455.1878209531. The cubic root of 647966587 is about 865.3348685075.

The spelling of 647966587 in words is "six hundred forty-seven million, nine hundred sixty-six thousand, five hundred eighty-seven".