636328121 has 16 divisors (see below), whose sum is σ = 773357760. Its totient is φ = 515565120.

The previous prime is 636328111. The next prime is 636328163. The reversal of 636328121 is 121823636.

It is a cyclic number.

It is not a de Polignac number, because 636328121 - 2¹⁸ = 636065977 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (636328111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72575 + ... + 80868.

It is an arithmetic number, because the mean of its divisors is an integer number (48334860).

Almost surely, 2^636328121 is an apocalyptic number.

It is an amenable number.

636328121 is a deficient number, since it is larger than the sum of its proper divisors (137029639).

636328121 is a wasteful number, since it uses less digits than its factorization.

636328121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153496.

The product of its digits is 10368, while the sum is 32.

The square root of 636328121 is about 25225.5450089785. The cubic root of 636328121 is about 860.1226258349.

The spelling of 636328121 in words is "six hundred thirty-six million, three hundred twenty-eight thousand, one hundred twenty-one".