66501101 has 4 divisors (see below), whose sum is σ = 66517500. Its totient is φ = 66484704.

The previous prime is 66501077. The next prime is 66501103. The reversal of 66501101 is 10110566.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 10110566 = 2 ⋅5055283.

It can be written as a sum of positive squares in 2 ways, for example, as 50779876 + 15721225 = 7126^2 + 3965^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66501101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66501103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2825 + ... + 11873.

It is an arithmetic number, because the mean of its divisors is an integer number (16629375).

Almost surely, 2^66501101 is an apocalyptic number.

It is an amenable number.

66501101 is a deficient number, since it is larger than the sum of its proper divisors (16399).

66501101 is an equidigital number, since it uses as much as digits as its factorization.

66501101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16398.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 66501101 is about 8154.8207215119. The cubic root of 66501101 is about 405.1441868360.

Adding to 66501101 its reverse (10110566), we get a palindrome (76611667).

The spelling of 66501101 in words is "sixty-six million, five hundred one thousand, one hundred one".