21641090380 has 192 divisors, whose sum is σ = 57392375040. Its totient is φ = 6672347136.

The previous prime is 21641090309. The next prime is 21641090411. The reversal of 21641090380 is 8309014612.

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, 15143506 + ... + 15144934.

It is an arithmetic number, because the mean of its divisors is an integer number (298918620).

Almost surely, 2^21641090380 is an apocalyptic number.

21641090380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21641090380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28696187520).

21641090380 is an abundant number, since it is smaller than the sum of its proper divisors (35751284660).

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

21641090380 is a wasteful number, since it uses less digits than its factorization.

21641090380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1668 (or 1666 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 34.

The spelling of 21641090380 in words is "twenty-one billion, six hundred forty-one million, ninety thousand, three hundred eighty".