21938273280 has 1056 divisors, whose sum is σ = 98711907840. Its totient is φ = 4538695680.

The previous prime is 21938273239. The next prime is 21938273293. The reversal of 21938273280 is 8237283912.

It is a tau number, because it is divible by the number of its divisors (1056).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 95800206 + ... + 95800434.

Almost surely, 2^21938273280 is an apocalyptic number.

21938273280 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 21938273280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49355953920).

21938273280 is an abundant number, since it is smaller than the sum of its proper divisors (76773634560).

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

21938273280 is a wasteful number, since it uses less digits than its factorization.

21938273280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287 (or 257 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The spelling of 21938273280 in words is "twenty-one billion, nine hundred thirty-eight million, two hundred seventy-three thousand, two hundred eighty".