66963791 has 2 divisors, whose sum is σ = 66963792. Its totient is φ = 66963790.

The previous prime is 66963781. The next prime is 66963803. The reversal of 66963791 is 19736966.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66963791 - 2¹⁰ = 66962767 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66963781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33481895 + 33481896.

It is an arithmetic number, because the mean of its divisors is an integer number (33481896).

Almost surely, 2^66963791 is an apocalyptic number.

66963791 is a deficient number, since it is larger than the sum of its proper divisors (1).

66963791 is an equidigital number, since it uses as much as digits as its factorization.

66963791 is an evil number, because the sum of its binary digits is even.

The product of its digits is 367416, while the sum is 47.

The square root of 66963791 is about 8183.1406562517. The cubic root of 66963791 is about 406.0816303948.

The spelling of 66963791 in words is "sixty-six million, nine hundred sixty-three thousand, seven hundred ninety-one".