20911025016 has 256 divisors, whose sum is σ = 70135296000. Its totient is φ = 5639310720.

The previous prime is 20911024987. The next prime is 20911025053. The reversal of 20911025016 is 61052011902.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8818311 + ... + 8820681.

It is an arithmetic number, because the mean of its divisors is an integer number (273966000).

Almost surely, 2^20911025016 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 20911025016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35067648000).

20911025016 is an abundant number, since it is smaller than the sum of its proper divisors (49224270984).

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

20911025016 is a wasteful number, since it uses less digits than its factorization.

20911025016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2719 (or 2709 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

Adding to 20911025016 its reverse (61052011902), we get a palindrome (81963036918).

The spelling of 20911025016 in words is "twenty billion, nine hundred eleven million, twenty-five thousand, sixteen".