66691383 has 16 divisors (see below), whose sum is σ = 97775616. Its totient is φ = 40098240.

The previous prime is 66691369. The next prime is 66691393. The reversal of 66691383 is 38319666.

It is not a de Polignac number, because 66691383 - 2⁸ = 66691127 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66691333) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3766 + ... + 12147.

It is an arithmetic number, because the mean of its divisors is an integer number (6110976).

Almost surely, 2^66691383 is an apocalyptic number.

66691383 is a deficient number, since it is larger than the sum of its proper divisors (31084233).

66691383 is a wasteful number, since it uses less digits than its factorization.

66691383 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16054.

The product of its digits is 139968, while the sum is 42.

The square root of 66691383 is about 8166.4792291415. The cubic root of 66691383 is about 405.5302367575.

The spelling of 66691383 in words is "sixty-six million, six hundred ninety-one thousand, three hundred eighty-three".