66587917 has 4 divisors (see below), whose sum is σ = 72641376. Its totient is φ = 60534460.

The previous prime is 66587897. The next prime is 66587923. The reversal of 66587917 is 71978566.

66587917 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 a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66587917 - 2⁷ = 66587789 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 (66587957) 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, 3026713 + ... + 3026734.

It is an arithmetic number, because the mean of its divisors is an integer number (18160344).

Almost surely, 2^66587917 is an apocalyptic number.

It is an amenable number.

66587917 is a deficient number, since it is larger than the sum of its proper divisors (6053459).

66587917 is a wasteful number, since it uses less digits than its factorization.

66587917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6053458.

The product of its digits is 635040, while the sum is 49.

The square root of 66587917 is about 8160.1419718042. The cubic root of 66587917 is about 405.3204130056.

The spelling of 66587917 in words is "sixty-six million, five hundred eighty-seven thousand, nine hundred seventeen".