66677791 has 6 divisors (see below), whose sum is σ = 70831040. Its totient is φ = 62755296.

The previous prime is 66677789. The next prime is 66677813. The reversal of 66677791 is 19777666.

It is not a de Polignac number, because 66677791 - 2¹ = 66677789 is a prime.

It is a super-3 number, since 3×66677791³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66677731) 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, 115071 + ... + 115648.

Almost surely, 2^66677791 is an apocalyptic number.

66677791 is a deficient number, since it is larger than the sum of its proper divisors (4153249).

66677791 is a wasteful number, since it uses less digits than its factorization.

66677791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230753 (or 230736 counting only the distinct ones).

The product of its digits is 666792, while the sum is 49.

The square root of 66677791 is about 8165.6470043714. The cubic root of 66677791 is about 405.5026852647.

The spelling of 66677791 in words is "sixty-six million, six hundred seventy-seven thousand, seven hundred ninety-one".