66345637 has 2 divisors, whose sum is σ = 66345638. Its totient is φ = 66345636.

The previous prime is 66345607. The next prime is 66345641. The reversal of 66345637 is 73654366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65707236 + 638401 = 8106^2 + 799^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66345637 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66345637.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66345607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33172818 + 33172819.

It is an arithmetic number, because the mean of its divisors is an integer number (33172819).

Almost surely, 2^66345637 is an apocalyptic number.

It is an amenable number.

66345637 is a deficient number, since it is larger than the sum of its proper divisors (1).

66345637 is an equidigital number, since it uses as much as digits as its factorization.

66345637 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 272160, while the sum is 40.

The square root of 66345637 is about 8145.2831135572. The cubic root of 66345637 is about 404.8282297546.

The spelling of 66345637 in words is "sixty-six million, three hundred forty-five thousand, six hundred thirty-seven".