66357491 has 2 divisors, whose sum is σ = 66357492. Its totient is φ = 66357490.

The previous prime is 66357439. The next prime is 66357497. The reversal of 66357491 is 19475366.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66357491 - 2⁶ = 66357427 is a prime.

It is a super-2 number, since 2×66357491² = 8806633223630162, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66357497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33178745 + 33178746.

It is an arithmetic number, because the mean of its divisors is an integer number (33178746).

Almost surely, 2^66357491 is an apocalyptic number.

66357491 is a deficient number, since it is larger than the sum of its proper divisors (1).

66357491 is an equidigital number, since it uses as much as digits as its factorization.

66357491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 136080, while the sum is 41.

The square root of 66357491 is about 8146.0107414611. The cubic root of 66357491 is about 404.8523385896.

The spelling of 66357491 in words is "sixty-six million, three hundred fifty-seven thousand, four hundred ninety-one".