64687817 has 2 divisors, whose sum is σ = 64687818. Its totient is φ = 64687816.

The previous prime is 64687783. The next prime is 64687829. The reversal of 64687817 is 71878646.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62425801 + 2262016 = 7901^2 + 1504^2 .

It is a cyclic number.

It is not a de Polignac number, because 64687817 - 2⁸ = 64687561 is a prime.

It is not a weakly prime, because it can be changed into another prime (64687517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32343908 + 32343909.

It is an arithmetic number, because the mean of its divisors is an integer number (32343909).

Almost surely, 2^64687817 is an apocalyptic number.

It is an amenable number.

64687817 is a deficient number, since it is larger than the sum of its proper divisors (1).

64687817 is an equidigital number, since it uses as much as digits as its factorization.

64687817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 451584, while the sum is 47.

The square root of 64687817 is about 8042.8736779835. The cubic root of 64687817 is about 401.4278491358.

The spelling of 64687817 in words is "sixty-four million, six hundred eighty-seven thousand, eight hundred seventeen".