20931449314656 has 192 divisors, whose sum is σ = 56425939416000. Its totient is φ = 6789975244800.

The previous prime is 20931449314649. The next prime is 20931449314687. The reversal of 20931449314656 is 65641394413902.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 20931449314596 and 20931449314605.

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 31 ways as a sum of consecutive naturals, for example, 2848200070 + ... + 2848207418.

It is an arithmetic number, because the mean of its divisors is an integer number (293885101125).

Almost surely, 2^{20931449314656} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20931449314656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28212969708000).

20931449314656 is an abundant number, since it is smaller than the sum of its proper divisors (35494490101344).

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

20931449314656 is a wasteful number, since it uses less digits than its factorization.

20931449314656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9113 (or 9105 counting only the distinct ones).

The product of its (nonzero) digits is 16796160, while the sum is 57.

The spelling of 20931449314656 in words is "twenty trillion, nine hundred thirty-one billion, four hundred forty-nine million, three hundred fourteen thousand, six hundred fifty-six".