21042260020 has 24 divisors (see below), whose sum is σ = 45128934144. Its totient is φ = 8237820576.

The previous prime is 21042260003. The next prime is 21042260023. The reversal of 21042260020 is 2006224012.

It is a self number, because there is not a number n which added to its sum of digits gives 21042260020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21042260023) by changing a digit.

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, 11191752 + ... + 11193631.

It is an arithmetic number, because the mean of its divisors is an integer number (1880372256).

Almost surely, 2^21042260020 is an apocalyptic number.

21042260020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21042260020 is an abundant number, since it is smaller than the sum of its proper divisors (24086674124).

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

21042260020 is a wasteful number, since it uses less digits than its factorization.

21042260020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22385439 (or 22385437 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 21042260020 its reverse (2006224012), we get a palindrome (23048484032).

The spelling of 21042260020 in words is "twenty-one billion, forty-two million, two hundred sixty thousand, twenty".