21481781683260 has 96 divisors (see below), whose sum is σ = 62129841629184. Its totient is φ = 5540063904000.

The previous prime is 21481781683253. The next prime is 21481781683273. The reversal of 21481781683260 is 6238618718412.

It is a super-2 number, since 2×21481781683260² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21481781683260.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 924171 + ... + 6619490.

It is an arithmetic number, because the mean of its divisors is an integer number (647185850304).

Almost surely, 2^{21481781683260} is an apocalyptic number.

21481781683260 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 21481781683260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31064920814592).

21481781683260 is an abundant number, since it is smaller than the sum of its proper divisors (40648059945924).

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

21481781683260 is a wasteful number, since it uses less digits than its factorization.

21481781683260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7545235 (or 7545233 counting only the distinct ones).

The product of its (nonzero) digits is 6193152, while the sum is 57.

The spelling of 21481781683260 in words is "twenty-one trillion, four hundred eighty-one billion, seven hundred eighty-one million, six hundred eighty-three thousand, two hundred sixty".