20731049920 has 224 divisors, whose sum is σ = 58329063936. Its totient is φ = 6870528000.

The previous prime is 20731049909. The next prime is 20731049921. The reversal of 20731049920 is 2994013702.

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 20731049920.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20731049921) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9727255 + ... + 9729385.

Almost surely, 2^20731049920 is an apocalyptic number.

20731049920 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 20731049920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29164531968).

20731049920 is an abundant number, since it is smaller than the sum of its proper divisors (37598014016).

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

20731049920 is a wasteful number, since it uses less digits than its factorization.

20731049920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2299 (or 2289 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 37.

The spelling of 20731049920 in words is "twenty billion, seven hundred thirty-one million, forty-nine thousand, nine hundred twenty".