438655561 has 2 divisors, whose sum is σ = 438655562. Its totient is φ = 438655560.

The previous prime is 438655541. The next prime is 438655571. The reversal of 438655561 is 165556834.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 343397961 + 95257600 = 18531^2 + 9760^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-438655561 is a prime.

It is not a weakly prime, because it can be changed into another prime (438655531) 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, 219327780 + 219327781.

It is an arithmetic number, because the mean of its divisors is an integer number (219327781).

Almost surely, 2^438655561 is an apocalyptic number.

It is an amenable number.

438655561 is a deficient number, since it is larger than the sum of its proper divisors (1).

438655561 is an equidigital number, since it uses as much as digits as its factorization.

438655561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432000, while the sum is 43.

The square root of 438655561 is about 20944.1056385800. The cubic root of 438655561 is about 759.8150294311.

The spelling of 438655561 in words is "four hundred thirty-eight million, six hundred fifty-five thousand, five hundred sixty-one".