66894563 has 2 divisors, whose sum is σ = 66894564. Its totient is φ = 66894562.

The previous prime is 66894547. The next prime is 66894571. The reversal of 66894563 is 36549866.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66894563 - 2⁴ = 66894547 is a prime.

It is not a weakly prime, because it can be changed into another prime (66894463) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33447281 + 33447282.

It is an arithmetic number, because the mean of its divisors is an integer number (33447282).

Almost surely, 2^66894563 is an apocalyptic number.

66894563 is a deficient number, since it is larger than the sum of its proper divisors (1).

66894563 is an equidigital number, since it uses as much as digits as its factorization.

66894563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 933120, while the sum is 47.

The square root of 66894563 is about 8178.9096461570. The cubic root of 66894563 is about 405.9416447307.

The spelling of 66894563 in words is "sixty-six million, eight hundred ninety-four thousand, five hundred sixty-three".