66868651 has 2 divisors, whose sum is σ = 66868652. Its totient is φ = 66868650.

The previous prime is 66868621. The next prime is 66868673. The reversal of 66868651 is 15686866.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66868651 - 2¹⁹ = 66344363 is a prime.

It is not a weakly prime, because it can be changed into another prime (66868601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33434325 + 33434326.

It is an arithmetic number, because the mean of its divisors is an integer number (33434326).

Almost surely, 2^66868651 is an apocalyptic number.

66868651 is a deficient number, since it is larger than the sum of its proper divisors (1).

66868651 is an equidigital number, since it uses as much as digits as its factorization.

66868651 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 414720, while the sum is 46.

The square root of 66868651 is about 8177.3254184972. The cubic root of 66868651 is about 405.8892233386.

It can be divided in two parts, 6686865 and 1, that added together give a palindrome (6686866).

The spelling of 66868651 in words is "sixty-six million, eight hundred sixty-eight thousand, six hundred fifty-one".