66983969 has 4 divisors (see below), whose sum is σ = 72136596. Its totient is φ = 61831344.

The previous prime is 66983957. The next prime is 66983971. The reversal of 66983969 is 96938966.

66983969 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 96938966 = 2 ⋅48469483.

It can be written as a sum of positive squares in 2 ways, for example, as 39526369 + 27457600 = 6287^2 + 5240^2 .

It is a cyclic number.

It is not a de Polignac number, because 66983969 - 2⁴ = 66983953 is a prime.

It is a super-2 number, since 2×66983969² = 8973704205985922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66983929) 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 in 3 ways as a sum of consecutive naturals, for example, 2576294 + ... + 2576319.

It is an arithmetic number, because the mean of its divisors is an integer number (18034149).

Almost surely, 2^66983969 is an apocalyptic number.

It is an amenable number.

66983969 is a deficient number, since it is larger than the sum of its proper divisors (5152627).

66983969 is a wasteful number, since it uses less digits than its factorization.

66983969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5152626.

The product of its digits is 3779136, while the sum is 56.

The square root of 66983969 is about 8184.3734641083. The cubic root of 66983969 is about 406.1224140887.

The spelling of 66983969 in words is "sixty-six million, nine hundred eighty-three thousand, nine hundred sixty-nine".