20999731200 has 288 divisors, whose sum is σ = 79343671680. Its totient is φ = 4799692800.

The previous prime is 20999731189. The next prime is 20999731237. The reversal of 20999731200 is 213799902.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1065435 + ... + 1084965.

It is an arithmetic number, because the mean of its divisors is an integer number (275498860).

Almost surely, 2^20999731200 is an apocalyptic number.

20999731200 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 20999731200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39671835840).

20999731200 is an abundant number, since it is smaller than the sum of its proper divisors (58343940480).

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

20999731200 is a wasteful number, since it uses less digits than its factorization.

20999731200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19573 (or 19548 counting only the distinct ones).

The product of its (nonzero) digits is 61236, while the sum is 42.

The spelling of 20999731200 in words is "twenty billion, nine hundred ninety-nine million, seven hundred thirty-one thousand, two hundred".