66397963 has 2 divisors, whose sum is σ = 66397964. Its totient is φ = 66397962.

The previous prime is 66397957. The next prime is 66397967. The reversal of 66397963 is 36979366.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66397963 - 2⁹ = 66397451 is a prime.

It is not a weakly prime, because it can be changed into another prime (66397967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33198981 + 33198982.

It is an arithmetic number, because the mean of its divisors is an integer number (33198982).

Almost surely, 2^66397963 is an apocalyptic number.

66397963 is a deficient number, since it is larger than the sum of its proper divisors (1).

66397963 is an equidigital number, since it uses as much as digits as its factorization.

66397963 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1102248, while the sum is 49.

The square root of 66397963 is about 8148.4945235301. The cubic root of 66397963 is about 404.9346294939.

The spelling of 66397963 in words is "sixty-six million, three hundred ninety-seven thousand, nine hundred sixty-three".