66894287 has 4 divisors (see below), whose sum is σ = 66918600. Its totient is φ = 66869976.

The previous prime is 66894251. The next prime is 66894319. The reversal of 66894287 is 78249866.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66894287 - 2¹⁸ = 66632143 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 (66894227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7412 + ... + 13737.

It is an arithmetic number, because the mean of its divisors is an integer number (16729650).

Almost surely, 2^66894287 is an apocalyptic number.

66894287 is a deficient number, since it is larger than the sum of its proper divisors (24313).

66894287 is a wasteful number, since it uses less digits than its factorization.

66894287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24312.

The product of its digits is 1161216, while the sum is 50.

The square root of 66894287 is about 8178.8927734749. The cubic root of 66894287 is about 405.9410864390.

The spelling of 66894287 in words is "sixty-six million, eight hundred ninety-four thousand, two hundred eighty-seven".