66635923 has 2 divisors, whose sum is σ = 66635924. Its totient is φ = 66635922.

The previous prime is 66635917. The next prime is 66635963. The reversal of 66635923 is 32953666.

It is a happy number.

It is an a-pointer prime, because the next prime (66635963) can be obtained adding 66635923 to its sum of digits (40).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66635923 is a prime.

It is not a weakly prime, because it can be changed into another prime (66635963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33317961 + 33317962.

It is an arithmetic number, because the mean of its divisors is an integer number (33317962).

Almost surely, 2^66635923 is an apocalyptic number.

66635923 is a deficient number, since it is larger than the sum of its proper divisors (1).

66635923 is an equidigital number, since it uses as much as digits as its factorization.

66635923 is an evil number, because the sum of its binary digits is even.

The product of its digits is 174960, while the sum is 40.

The square root of 66635923 is about 8163.0829347741. The cubic root of 66635923 is about 405.4177937243.

The spelling of 66635923 in words is "sixty-six million, six hundred thirty-five thousand, nine hundred twenty-three".