11646631621 has 2 divisors, whose sum is σ = 11646631622. Its totient is φ = 11646631620.

The previous prime is 11646631589. The next prime is 11646631669. The reversal of 11646631621 is 12613664611.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11355246721 + 291384900 = 106561^2 + 17070^2 .

It is a cyclic number.

It is not a de Polignac number, because 11646631621 - 2⁵ = 11646631589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11646631021) 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 as a sum of consecutive naturals, namely, 5823315810 + 5823315811.

It is an arithmetic number, because the mean of its divisors is an integer number (5823315811).

Almost surely, 2^11646631621 is an apocalyptic number.

It is an amenable number.

11646631621 is a deficient number, since it is larger than the sum of its proper divisors (1).

11646631621 is an equidigital number, since it uses as much as digits as its factorization.

11646631621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31104, while the sum is 37.

The spelling of 11646631621 in words is "eleven billion, six hundred forty-six million, six hundred thirty-one thousand, six hundred twenty-one".