11621664217 has 4 divisors (see below), whose sum is σ = 11624059876. Its totient is φ = 11619268560.

The previous prime is 11621664211. The next prime is 11621664239. The reversal of 11621664217 is 71246612611.

11621664217 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8009534016 + 3612130201 = 89496^2 + 60101^2 .

It is a cyclic number.

It is not a de Polignac number, because 11621664217 - 2¹⁵ = 11621631449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11621664211) 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 3 ways as a sum of consecutive naturals, for example, 1190538 + ... + 1200259.

It is an arithmetic number, because the mean of its divisors is an integer number (2906014969).

Almost surely, 2^11621664217 is an apocalyptic number.

It is an amenable number.

11621664217 is a deficient number, since it is larger than the sum of its proper divisors (2395659).

11621664217 is an equidigital number, since it uses as much as digits as its factorization.

11621664217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2395658.

The product of its digits is 24192, while the sum is 37.

The spelling of 11621664217 in words is "eleven billion, six hundred twenty-one million, six hundred sixty-four thousand, two hundred seventeen".