21989231040 has 224 divisors, whose sum is σ = 80566686720. Its totient is φ = 4977156096.

The previous prime is 21989231027. The next prime is 21989231057. The reversal of 21989231040 is 4013298912.

It is a tau number, because it is divible by the number of its divisors (224).

It is a self number, because there is not a number n which added to its sum of digits gives 21989231040.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 676276 + ... + 708044.

Almost surely, 2^21989231040 is an apocalyptic number.

21989231040 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 21989231040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40283343360).

21989231040 is an abundant number, since it is smaller than the sum of its proper divisors (58577455680).

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

21989231040 is a wasteful number, since it uses less digits than its factorization.

21989231040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31899 (or 31889 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 39.

The spelling of 21989231040 in words is "twenty-one billion, nine hundred eighty-nine million, two hundred thirty-one thousand, forty".