66574861 has 2 divisors, whose sum is σ = 66574862. Its totient is φ = 66574860.

The previous prime is 66574847. The next prime is 66574897. The reversal of 66574861 is 16847566.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35772361 + 30802500 = 5981^2 + 5550^2 .

It is a cyclic number.

It is not a de Polignac number, because 66574861 - 2⁷ = 66574733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66574831) 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, 33287430 + 33287431.

It is an arithmetic number, because the mean of its divisors is an integer number (33287431).

Almost surely, 2^66574861 is an apocalyptic number.

It is an amenable number.

66574861 is a deficient number, since it is larger than the sum of its proper divisors (1).

66574861 is an equidigital number, since it uses as much as digits as its factorization.

66574861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 241920, while the sum is 43.

The square root of 66574861 is about 8159.3419465052. The cubic root of 66574861 is about 405.2939206656.

The spelling of 66574861 in words is "sixty-six million, five hundred seventy-four thousand, eight hundred sixty-one".