66369491 has 2 divisors, whose sum is σ = 66369492. Its totient is φ = 66369490.

The previous prime is 66369473. The next prime is 66369493. The reversal of 66369491 is 19496366.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66369491 - 2⁶ = 66369427 is a prime.

Together with 66369493, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66369493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33184745 + 33184746.

It is an arithmetic number, because the mean of its divisors is an integer number (33184746).

Almost surely, 2^66369491 is an apocalyptic number.

66369491 is a deficient number, since it is larger than the sum of its proper divisors (1).

66369491 is an equidigital number, since it uses as much as digits as its factorization.

66369491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 209952, while the sum is 44.

The square root of 66369491 is about 8146.7472650132. The cubic root of 66369491 is about 404.8767414373.

The spelling of 66369491 in words is "sixty-six million, three hundred sixty-nine thousand, four hundred ninety-one".