21115526880 has 288 divisors, whose sum is σ = 81447327360. Its totient is φ = 4572288000.

The previous prime is 21115526867. The next prime is 21115526881. The reversal of 21115526880 is 8862551112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21115526881) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 423255 + ... + 470505.

It is an arithmetic number, because the mean of its divisors is an integer number (282803220).

Almost surely, 2^21115526880 is an apocalyptic number.

21115526880 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 21115526880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40723663680).

21115526880 is an abundant number, since it is smaller than the sum of its proper divisors (60331800480).

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

21115526880 is a wasteful number, since it uses less digits than its factorization.

21115526880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47302 (or 47287 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 39.

The spelling of 21115526880 in words is "twenty-one billion, one hundred fifteen million, five hundred twenty-six thousand, eight hundred eighty".