21421421124 has 24 divisors (see below), whose sum is σ = 50003711520. Its totient is φ = 7137560064.

The previous prime is 21421421111. The next prime is 21421421141. The reversal of 21421421124 is 42112412412.

It is a happy number.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 21421421094 and 21421421103.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 333469 + ... + 392484.

It is an arithmetic number, because the mean of its divisors is an integer number (2083487980).

Almost surely, 2^21421421124 is an apocalyptic number.

It is an amenable number.

21421421124 is an abundant number, since it is smaller than the sum of its proper divisors (28582290396).

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

21421421124 is a wasteful number, since it uses less digits than its factorization.

21421421124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 728419 (or 728417 counting only the distinct ones).

The product of its digits is 1024, while the sum is 24.

Adding to 21421421124 its reverse (42112412412), we get a palindrome (63533833536).

The spelling of 21421421124 in words is "twenty-one billion, four hundred twenty-one million, four hundred twenty-one thousand, one hundred twenty-four".