66523393 has 2 divisors, whose sum is σ = 66523394. Its totient is φ = 66523392.

The previous prime is 66523349. The next prime is 66523403. The reversal of 66523393 is 39332566.

66523393 is nontrivially palindromic in base 9.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66471409 + 51984 = 8153^2 + 228^2 .

It is a cyclic number.

It is not a de Polignac number, because 66523393 - 2⁹ = 66522881 is a prime.

It is not a weakly prime, because it can be changed into another prime (66523493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33261696 + 33261697.

It is an arithmetic number, because the mean of its divisors is an integer number (33261697).

Almost surely, 2^66523393 is an apocalyptic number.

It is an amenable number.

66523393 is a deficient number, since it is larger than the sum of its proper divisors (1).

66523393 is an equidigital number, since it uses as much as digits as its factorization.

66523393 is an evil number, because the sum of its binary digits is even.

The product of its digits is 87480, while the sum is 37.

The square root of 66523393 is about 8156.1874058901. The cubic root of 66523393 is about 405.1894515766.

The spelling of 66523393 in words is "sixty-six million, five hundred twenty-three thousand, three hundred ninety-three".