21972787200 has 1008 divisors, whose sum is σ = 97609127616. Its totient is φ = 4600627200.

The previous prime is 21972787189. The next prime is 21972787201. The reversal of 21972787200 is 278727912.

It is a tau number, because it is divible by the number of its divisors (1008).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (21972787201) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 167731135 + ... + 167731265.

It is an arithmetic number, because the mean of its divisors is an integer number (96834452).

Almost surely, 2^21972787200 is an apocalyptic number.

21972787200 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 21972787200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48804563808).

21972787200 is an abundant number, since it is smaller than the sum of its proper divisors (75636340416).

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

21972787200 is a wasteful number, since it uses less digits than its factorization.

21972787200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 197568, while the sum is 45.

The spelling of 21972787200 in words is "twenty-one billion, nine hundred seventy-two million, seven hundred eighty-seven thousand, two hundred".