21430441980 has 144 divisors (see below), whose sum is σ = 67188086784. Its totient is φ = 5523396480.

The previous prime is 21430441979. The next prime is 21430442009. The reversal of 21430441980 is 8914403412.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5483187 + ... + 5487093.

It is an arithmetic number, because the mean of its divisors is an integer number (466583936).

Almost surely, 2^21430441980 is an apocalyptic number.

21430441980 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 21430441980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33594043392).

21430441980 is an abundant number, since it is smaller than the sum of its proper divisors (45757644804).

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

21430441980 is a wasteful number, since it uses less digits than its factorization.

21430441980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4936 (or 4931 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The spelling of 21430441980 in words is "twenty-one billion, four hundred thirty million, four hundred forty-one thousand, nine hundred eighty".