21126421140 has 48 divisors (see below), whose sum is σ = 64531615680. Its totient is φ = 5121556480.

The previous prime is 21126421139. The next prime is 21126421159. The reversal of 21126421140 is 4112462112.

It is a self number, because there is not a number n which added to its sum of digits gives 21126421140.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16004205 + ... + 16005524.

It is an arithmetic number, because the mean of its divisors is an integer number (1344408660).

Almost surely, 2^21126421140 is an apocalyptic number.

21126421140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21126421140 is an abundant number, since it is smaller than the sum of its proper divisors (43405194540).

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

21126421140 is a wasteful number, since it uses less digits than its factorization.

21126421140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32009752 (or 32009750 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

Adding to 21126421140 its reverse (4112462112), we get a palindrome (25238883252).

The spelling of 21126421140 in words is "twenty-one billion, one hundred twenty-six million, four hundred twenty-one thousand, one hundred forty".