63945809 has 2 divisors, whose sum is σ = 63945810. Its totient is φ = 63945808.

The previous prime is 63945797. The next prime is 63945829. The reversal of 63945809 is 90854936.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62457409 + 1488400 = 7903^2 + 1220^2 .

It is a cyclic number.

It is not a de Polignac number, because 63945809 - 2¹⁶ = 63880273 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 63945809.

It is not a weakly prime, because it can be changed into another prime (63945829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31972904 + 31972905.

It is an arithmetic number, because the mean of its divisors is an integer number (31972905).

Almost surely, 2^63945809 is an apocalyptic number.

It is an amenable number.

63945809 is a deficient number, since it is larger than the sum of its proper divisors (1).

63945809 is an equidigital number, since it uses as much as digits as its factorization.

63945809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 233280, while the sum is 44.

The square root of 63945809 is about 7996.6123452372. The cubic root of 63945809 is about 399.8870702035.

The spelling of 63945809 in words is "sixty-three million, nine hundred forty-five thousand, eight hundred nine".