66767391 has 6 divisors (see below), whose sum is σ = 96441800. Its totient is φ = 44511588.

The previous prime is 66767383. The next prime is 66767417. The reversal of 66767391 is 19376766.

It is not a de Polignac number, because 66767391 - 2³ = 66767383 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66767791) 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 in 5 ways as a sum of consecutive naturals, for example, 3709291 + ... + 3709308.

Almost surely, 2^66767391 is an apocalyptic number.

66767391 is a deficient number, since it is larger than the sum of its proper divisors (29674409).

66767391 is a wasteful number, since it uses less digits than its factorization.

66767391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7418605 (or 7418602 counting only the distinct ones).

The product of its digits is 285768, while the sum is 45.

The square root of 66767391 is about 8171.1315617851. The cubic root of 66767391 is about 405.6842388610.

The spelling of 66767391 in words is "sixty-six million, seven hundred sixty-seven thousand, three hundred ninety-one".