21283709980 has 96 divisors (see below), whose sum is σ = 51115893696. Its totient is φ = 7374483456.

The previous prime is 21283709977. The next prime is 21283710013. The reversal of 21283709980 is 8990738212.

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 1526802 + ... + 1540678.

It is an arithmetic number, because the mean of its divisors is an integer number (532457226).

Almost surely, 2^21283709980 is an apocalyptic number.

21283709980 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21283709980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25557946848).

21283709980 is an abundant number, since it is smaller than the sum of its proper divisors (29832183716).

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

21283709980 is a wasteful number, since it uses less digits than its factorization.

21283709980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14263 (or 14261 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 49.

The spelling of 21283709980 in words is "twenty-one billion, two hundred eighty-three million, seven hundred nine thousand, nine hundred eighty".