21681088950 has 144 divisors (see below), whose sum is σ = 55668789648. Its totient is φ = 5582304000.

The previous prime is 21681088939. The next prime is 21681088963. The reversal of 21681088950 is 5988018612.

It is a self number, because there is not a number n which added to its sum of digits gives 21681088950.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 40075680 + ... + 40076220.

It is an arithmetic number, because the mean of its divisors is an integer number (386588817).

Almost surely, 2^21681088950 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21681088950, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27834394824).

21681088950 is an abundant number, since it is smaller than the sum of its proper divisors (33987700698).

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

21681088950 is a wasteful number, since it uses less digits than its factorization.

21681088950 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 751 (or 675 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 48.

The spelling of 21681088950 in words is "twenty-one billion, six hundred eighty-one million, eighty-eight thousand, nine hundred fifty".