21241990420 has 48 divisors (see below), whose sum is σ = 51144807168. Its totient is φ = 7259535360.

The previous prime is 21241990397. The next prime is 21241990459. The reversal of 21241990420 is 2409914212.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 200397 + ... + 287476.

It is an arithmetic number, because the mean of its divisors is an integer number (1065516816).

Almost surely, 2^21241990420 is an apocalyptic number.

21241990420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21241990420 is an abundant number, since it is smaller than the sum of its proper divisors (29902816748).

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

21241990420 is a wasteful number, since it uses less digits than its factorization.

21241990420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 488200 (or 488198 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 34.

The spelling of 21241990420 in words is "twenty-one billion, two hundred forty-one million, nine hundred ninety thousand, four hundred twenty".