66210101 has 2 divisors, whose sum is σ = 66210102. Its totient is φ = 66210100.

The previous prime is 66210061. The next prime is 66210113. The reversal of 66210101 is 10101266.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 37576900 + 28633201 = 6130^2 + 5351^2 .

It is a cyclic number.

It is not a de Polignac number, because 66210101 - 2¹⁴ = 66193717 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66210101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66210181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33105050 + 33105051.

It is an arithmetic number, because the mean of its divisors is an integer number (33105051).

Almost surely, 2^66210101 is an apocalyptic number.

It is an amenable number.

66210101 is a deficient number, since it is larger than the sum of its proper divisors (1).

66210101 is an equidigital number, since it uses as much as digits as its factorization.

66210101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 66210101 is about 8136.9589528275. The cubic root of 66210101 is about 404.5523703446.

Adding to 66210101 its reverse (10101266), we get a palindrome (76311367).

The spelling of 66210101 in words is "sixty-six million, two hundred ten thousand, one hundred one".