66838973 has 2 divisors, whose sum is σ = 66838974. Its totient is φ = 66838972.

The previous prime is 66838963. The next prime is 66839023. The reversal of 66838973 is 37983866.

It is an a-pointer prime, because the next prime (66839023) can be obtained adding 66838973 to its sum of digits (50).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49182169 + 17656804 = 7013^2 + 4202^2 .

It is a cyclic number.

It is not a de Polignac number, because 66838973 - 2¹² = 66834877 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66838913) 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, 33419486 + 33419487.

It is an arithmetic number, because the mean of its divisors is an integer number (33419487).

Almost surely, 2^66838973 is an apocalyptic number.

It is an amenable number.

66838973 is a deficient number, since it is larger than the sum of its proper divisors (1).

66838973 is an equidigital number, since it uses as much as digits as its factorization.

66838973 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1306368, while the sum is 50.

The square root of 66838973 is about 8175.5105650962. The cubic root of 66838973 is about 405.8291664822.

The spelling of 66838973 in words is "sixty-six million, eight hundred thirty-eight thousand, nine hundred seventy-three".