66609503 has 2 divisors, whose sum is σ = 66609504. Its totient is φ = 66609502.

The previous prime is 66609493. The next prime is 66609523. The reversal of 66609503 is 30590666.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66609503 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66609523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33304751 + 33304752.

It is an arithmetic number, because the mean of its divisors is an integer number (33304752).

Almost surely, 2^66609503 is an apocalyptic number.

66609503 is a deficient number, since it is larger than the sum of its proper divisors (1).

66609503 is an equidigital number, since it uses as much as digits as its factorization.

66609503 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 29160, while the sum is 35.

The square root of 66609503 is about 8161.4645131863. The cubic root of 66609503 is about 405.3642062421.

The spelling of 66609503 in words is "sixty-six million, six hundred nine thousand, five hundred three".