21661053322326 has 48 divisors (see below), whose sum is σ = 47621583347184. Its totient is φ = 6563532448000.

The previous prime is 21661053322313. The next prime is 21661053322387. The reversal of 21661053322326 is 62322335016612.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10401586 + ... + 12309146.

It is an arithmetic number, because the mean of its divisors is an integer number (992116319733).

Almost surely, 2^{21661053322326} is an apocalyptic number.

21661053322326 is an abundant number, since it is smaller than the sum of its proper divisors (25960530024858).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21661053322326 is a wasteful number, since it uses less digits than its factorization.

21661053322326 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1923229 (or 1923218 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 42.

Adding to 21661053322326 its reverse (62322335016612), we get a palindrome (83983388338938).

The spelling of 21661053322326 in words is "twenty-one trillion, six hundred sixty-one billion, fifty-three million, three hundred twenty-two thousand, three hundred twenty-six".