64442561 has 2 divisors, whose sum is σ = 64442562. Its totient is φ = 64442560.

The previous prime is 64442557. The next prime is 64442633. The reversal of 64442561 is 16524446.

64442561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55591936 + 8850625 = 7456^2 + 2975^2 .

It is a cyclic number.

It is not a de Polignac number, because 64442561 - 2² = 64442557 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (64442551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32221280 + 32221281.

It is an arithmetic number, because the mean of its divisors is an integer number (32221281).

Almost surely, 2^64442561 is an apocalyptic number.

It is an amenable number.

64442561 is a deficient number, since it is larger than the sum of its proper divisors (1).

64442561 is an equidigital number, since it uses as much as digits as its factorization.

64442561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23040, while the sum is 32.

The square root of 64442561 is about 8027.6124096770. The cubic root of 64442561 is about 400.9198849907.

The spelling of 64442561 in words is "sixty-four million, four hundred forty-two thousand, five hundred sixty-one".