66444437 has 2 divisors, whose sum is σ = 66444438. Its totient is φ = 66444436.

The previous prime is 66444431. The next prime is 66444461. The reversal of 66444437 is 73444466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40627876 + 25816561 = 6374^2 + 5081^2 .

It is a cyclic number.

It is not a de Polignac number, because 66444437 - 2⁴ = 66444421 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 66444437.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66444431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33222218 + 33222219.

It is an arithmetic number, because the mean of its divisors is an integer number (33222219).

Almost surely, 2^66444437 is an apocalyptic number.

It is an amenable number.

66444437 is a deficient number, since it is larger than the sum of its proper divisors (1).

66444437 is an equidigital number, since it uses as much as digits as its factorization.

66444437 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 193536, while the sum is 38.

The square root of 66444437 is about 8151.3457171194. The cubic root of 66444437 is about 405.0290829087.

The spelling of 66444437 in words is "sixty-six million, four hundred forty-four thousand, four hundred thirty-seven".