65554721 has 2 divisors, whose sum is σ = 65554722. Its totient is φ = 65554720.

The previous prime is 65554711. The next prime is 65554751. The reversal of 65554721 is 12745556.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64320400 + 1234321 = 8020^2 + 1111^2 .

It is a cyclic number.

It is not a de Polignac number, because 65554721 - 2¹⁴ = 65538337 is a prime.

It is not a weakly prime, because it can be changed into another prime (65554711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32777360 + 32777361.

It is an arithmetic number, because the mean of its divisors is an integer number (32777361).

Almost surely, 2^65554721 is an apocalyptic number.

It is an amenable number.

65554721 is a deficient number, since it is larger than the sum of its proper divisors (1).

65554721 is an equidigital number, since it uses as much as digits as its factorization.

65554721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42000, while the sum is 35.

The square root of 65554721 is about 8096.5869970006. The cubic root of 65554721 is about 403.2131225816.

The spelling of 65554721 in words is "sixty-five million, five hundred fifty-four thousand, seven hundred twenty-one".