66616201 has 2 divisors, whose sum is σ = 66616202. Its totient is φ = 66616200.

The previous prime is 66616189. The next prime is 66616259. The reversal of 66616201 is 10261666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55890576 + 10725625 = 7476^2 + 3275^2 .

It is a cyclic number.

It is not a de Polignac number, because 66616201 - 2¹¹ = 66614153 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66616201.

It is not a weakly prime, because it can be changed into another prime (66616271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33308100 + 33308101.

It is an arithmetic number, because the mean of its divisors is an integer number (33308101).

Almost surely, 2^66616201 is an apocalyptic number.

It is an amenable number.

66616201 is a deficient number, since it is larger than the sum of its proper divisors (1).

66616201 is an equidigital number, since it uses as much as digits as its factorization.

66616201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 66616201 is about 8161.8748458917. The cubic root of 66616201 is about 405.3777930844.

Adding to 66616201 its reverse (10261666), we get a palindrome (76877867).

The spelling of 66616201 in words is "sixty-six million, six hundred sixteen thousand, two hundred one".