66684078437 has 2 divisors, whose sum is σ = 66684078438. Its totient is φ = 66684078436.

The previous prime is 66684078431. The next prime is 66684078443. The reversal of 66684078437 is 73487048666.

It is a balanced prime because it is at equal distance from previous prime (66684078431) and next prime (66684078443).

It can be written as a sum of positive squares in only one way, i.e., 44447602276 + 22236476161 = 210826^2 + 149119^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66684078437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66684078431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33342039218 + 33342039219.

It is an arithmetic number, because the mean of its divisors is an integer number (33342039219).

Almost surely, 2^66684078437 is an apocalyptic number.

It is an amenable number.

66684078437 is a deficient number, since it is larger than the sum of its proper divisors (1).

66684078437 is an equidigital number, since it uses as much as digits as its factorization.

66684078437 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32514048, while the sum is 59.

The spelling of 66684078437 in words is "sixty-six billion, six hundred eighty-four million, seventy-eight thousand, four hundred thirty-seven".