21899199616 has 128 divisors (see below), whose sum is σ = 51233212800. Its totient is φ = 9128706048.

The previous prime is 21899199589. The next prime is 21899199677. The reversal of 21899199616 is 61699199812.

It is a tau number, because it is divible by the number of its divisors (128).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10362976 + ... + 10365088.

It is an arithmetic number, because the mean of its divisors is an integer number (400259475).

Almost surely, 2^21899199616 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 21899199616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25616606400).

21899199616 is an abundant number, since it is smaller than the sum of its proper divisors (29334013184).

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

21899199616 is a wasteful number, since it uses less digits than its factorization.

21899199616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2446 (or 2434 counting only the distinct ones).

The product of its digits is 3779136, while the sum is 61.

The spelling of 21899199616 in words is "twenty-one billion, eight hundred ninety-nine million, one hundred ninety-nine thousand, six hundred sixteen".