66674691 has 8 divisors (see below), whose sum is σ = 98777360. Its totient is φ = 44449776.

The previous prime is 66674687. The next prime is 66674753. The reversal of 66674691 is 19647666.

It is a happy number.

It is not a de Polignac number, because 66674691 - 2² = 66674687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66674611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1234690 + ... + 1234743.

It is an arithmetic number, because the mean of its divisors is an integer number (12347170).

Almost surely, 2^66674691 is an apocalyptic number.

66674691 is a deficient number, since it is larger than the sum of its proper divisors (32102669).

66674691 is a wasteful number, since it uses less digits than its factorization.

66674691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2469442 (or 2469436 counting only the distinct ones).

The product of its digits is 326592, while the sum is 45.

The square root of 66674691 is about 8165.4571825465. The cubic root of 66674691 is about 405.4964009243.

It can be divided in two parts, 666 and 74691, that added together give a palindrome (75357).

The spelling of 66674691 in words is "sixty-six million, six hundred seventy-four thousand, six hundred ninety-one".