63956561 has 2 divisors, whose sum is σ = 63956562. Its totient is φ = 63956560.

The previous prime is 63956551. The next prime is 63956591. The reversal of 63956561 is 16565936.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42510400 + 21446161 = 6520^2 + 4631^2 .

It is a cyclic number.

It is not a de Polignac number, because 63956561 - 2¹⁸ = 63694417 is a prime.

It is not a weakly prime, because it can be changed into another prime (63956551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31978280 + 31978281.

It is an arithmetic number, because the mean of its divisors is an integer number (31978281).

Almost surely, 2^63956561 is an apocalyptic number.

It is an amenable number.

63956561 is a deficient number, since it is larger than the sum of its proper divisors (1).

63956561 is an equidigital number, since it uses as much as digits as its factorization.

63956561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145800, while the sum is 41.

The square root of 63956561 is about 7997.2846016632. The cubic root of 63956561 is about 399.9094816009.

The spelling of 63956561 in words is "sixty-three million, nine hundred fifty-six thousand, five hundred sixty-one".