66893987 has 2 divisors, whose sum is σ = 66893988. Its totient is φ = 66893986.

The previous prime is 66893969. The next prime is 66894007. The reversal of 66893987 is 78939866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66893987 - 2⁸ = 66893731 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66893287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33446993 + 33446994.

It is an arithmetic number, because the mean of its divisors is an integer number (33446994).

Almost surely, 2^66893987 is an apocalyptic number.

66893987 is a deficient number, since it is larger than the sum of its proper divisors (1).

66893987 is an equidigital number, since it uses as much as digits as its factorization.

66893987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3919104, while the sum is 56.

The square root of 66893987 is about 8178.8744335636. The cubic root of 66893987 is about 405.9404795984.

The spelling of 66893987 in words is "sixty-six million, eight hundred ninety-three thousand, nine hundred eighty-seven".