66303121 has 4 divisors (see below), whose sum is σ = 66320100. Its totient is φ = 66286144.

The previous prime is 66303113. The next prime is 66303143. The reversal of 66303121 is 12130366.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12130366 = 2 ⋅6065183.

It can be written as a sum of positive squares in 2 ways, for example, as 7182400 + 59120721 = 2680^2 + 7689^2 .

It is a cyclic number.

It is not a de Polignac number, because 66303121 - 2³ = 66303113 is a prime.

It is a super-2 number, since 2×66303121² = 8792207708681282, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66303092 and 66303101.

It is not an unprimeable number, because it can be changed into a prime (66303101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 645 + ... + 11533.

It is an arithmetic number, because the mean of its divisors is an integer number (16580025).

Almost surely, 2^66303121 is an apocalyptic number.

It is an amenable number.

66303121 is a deficient number, since it is larger than the sum of its proper divisors (16979).

66303121 is a wasteful number, since it uses less digits than its factorization.

66303121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16978.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 66303121 is about 8142.6728412727. The cubic root of 66303121 is about 404.7417364765.

Adding to 66303121 its reverse (12130366), we get a palindrome (78433487).

The spelling of 66303121 in words is "sixty-six million, three hundred three thousand, one hundred twenty-one".