21481288840 has 64 divisors (see below), whose sum is σ = 55019295360. Its totient is φ = 7471749120.

The previous prime is 21481288837. The next prime is 21481288867. The reversal of 21481288840 is 4888218412.

It is a super-3 number, since 3×21481288840³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (46).

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 15 ways as a sum of consecutive naturals, for example, 1051209 + ... + 1071448.

It is an arithmetic number, because the mean of its divisors is an integer number (859676490).

Almost surely, 2^21481288840 is an apocalyptic number.

21481288840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21481288840 is an abundant number, since it is smaller than the sum of its proper divisors (33538006520).

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

21481288840 is a wasteful number, since it uses less digits than its factorization.

21481288840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2122702 (or 2122698 counting only the distinct ones).

The product of its (nonzero) digits is 262144, while the sum is 46.

The spelling of 21481288840 in words is "twenty-one billion, four hundred eighty-one million, two hundred eighty-eight thousand, eight hundred forty".