66671851 has 2 divisors, whose sum is σ = 66671852. Its totient is φ = 66671850.

The previous prime is 66671837. The next prime is 66671861. The reversal of 66671851 is 15817666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66671851 - 2⁷ = 66671723 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66671831) 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, 33335925 + 33335926.

It is an arithmetic number, because the mean of its divisors is an integer number (33335926).

Almost surely, 2^66671851 is an apocalyptic number.

66671851 is a deficient number, since it is larger than the sum of its proper divisors (1).

66671851 is an equidigital number, since it uses as much as digits as its factorization.

66671851 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 60480, while the sum is 40.

The square root of 66671851 is about 8165.2832773885. The cubic root of 66671851 is about 405.4906434866.

The spelling of 66671851 in words is "sixty-six million, six hundred seventy-one thousand, eight hundred fifty-one".