66308121 has 18 divisors (see below), whose sum is σ = 105278810. Its totient is φ = 40186080.

The previous prime is 66308093. The next prime is 66308167. The reversal of 66308121 is 12180366.

66308121 is a `hidden beast` number, since 6 + 630 + 8 + 1 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 40144896 + 26163225 = 6336^2 + 5115^2 .

It is not a de Polignac number, because 66308121 - 2¹³ = 66299929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66301121) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 29356 + ... + 31533.

Almost surely, 2^66308121 is an apocalyptic number.

It is an amenable number.

66308121 is a deficient number, since it is larger than the sum of its proper divisors (38970689).

66308121 is a wasteful number, since it uses less digits than its factorization.

66308121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60917 (or 60903 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 66308121 is about 8142.9798599776. The cubic root of 66308121 is about 404.7519102450.

Adding to 66308121 its reverse (12180366), we get a palindrome (78488487).

The spelling of 66308121 in words is "sixty-six million, three hundred eight thousand, one hundred twenty-one".