648464989 has 2 divisors, whose sum is σ = 648464990. Its totient is φ = 648464988.

The previous prime is 648464951. The next prime is 648465007. The reversal of 648464989 is 989464846.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 565964100 + 82500889 = 23790^2 + 9083^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-648464989 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (648464189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324232494 + 324232495.

It is an arithmetic number, because the mean of its divisors is an integer number (324232495).

Almost surely, 2^648464989 is an apocalyptic number.

It is an amenable number.

648464989 is a deficient number, since it is larger than the sum of its proper divisors (1).

648464989 is an equidigital number, since it uses as much as digits as its factorization.

648464989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11943936, while the sum is 58.

The square root of 648464989 is about 25464.9757313845. The cubic root of 648464989 is about 865.5566773203.

The spelling of 648464989 in words is "six hundred forty-eight million, four hundred sixty-four thousand, nine hundred eighty-nine".