21084810240 has 352 divisors, whose sum is σ = 75800180736. Its totient is φ = 4963368960.

The previous prime is 21084810181. The next prime is 21084810293. The reversal of 21084810240 is 4201848012.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 21084810198 and 21084810207.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4590345 + ... + 4594935.

Almost surely, 2^21084810240 is an apocalyptic number.

21084810240 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 21084810240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37900090368).

21084810240 is an abundant number, since it is smaller than the sum of its proper divisors (54715370496).

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

21084810240 is a wasteful number, since it uses less digits than its factorization.

21084810240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4655 (or 4637 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 30.

The spelling of 21084810240 in words is "twenty-one billion, eighty-four million, eight hundred ten thousand, two hundred forty".