21101910984 has 192 divisors, whose sum is σ = 71430353280. Its totient is φ = 5467392000.

The previous prime is 21101910979. The next prime is 21101910997. The reversal of 21101910984 is 48901910112.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2329504 + ... + 2338544.

It is an arithmetic number, because the mean of its divisors is an integer number (372033090).

Almost surely, 2^21101910984 is an apocalyptic number.

21101910984 is a gapful number since it is divisible by the number (24) 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 21101910984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35715176640).

21101910984 is an abundant number, since it is smaller than the sum of its proper divisors (50328442296).

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

21101910984 is a wasteful number, since it uses less digits than its factorization.

21101910984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9492 (or 9485 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The spelling of 21101910984 in words is "twenty-one billion, one hundred one million, nine hundred ten thousand, nine hundred eighty-four".