66657803 has 2 divisors, whose sum is σ = 66657804. Its totient is φ = 66657802.

The previous prime is 66657769. The next prime is 66657821. The reversal of 66657803 is 30875666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66657803 - 2⁶ = 66657739 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (66657823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33328901 + 33328902.

It is an arithmetic number, because the mean of its divisors is an integer number (33328902).

Almost surely, 2^66657803 is an apocalyptic number.

66657803 is a deficient number, since it is larger than the sum of its proper divisors (1).

66657803 is an equidigital number, since it uses as much as digits as its factorization.

66657803 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 181440, while the sum is 41.

The square root of 66657803 is about 8164.4230047199. The cubic root of 66657803 is about 405.4621620381.

The spelling of 66657803 in words is "sixty-six million, six hundred fifty-seven thousand, eight hundred three".