66995587 has 2 divisors, whose sum is σ = 66995588. Its totient is φ = 66995586.

The previous prime is 66995561. The next prime is 66995609. The reversal of 66995587 is 78559966.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66995587 - 2¹¹ = 66993539 is a prime.

It is not a weakly prime, because it can be changed into another prime (66995287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33497793 + 33497794.

It is an arithmetic number, because the mean of its divisors is an integer number (33497794).

Almost surely, 2^66995587 is an apocalyptic number.

66995587 is a deficient number, since it is larger than the sum of its proper divisors (1).

66995587 is an equidigital number, since it uses as much as digits as its factorization.

66995587 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4082400, while the sum is 55.

The square root of 66995587 is about 8185.0832005545. The cubic root of 66995587 is about 406.1458926290.

The spelling of 66995587 in words is "sixty-six million, nine hundred ninety-five thousand, five hundred eighty-seven".