21027373440 has 512 divisors, whose sum is σ = 73763136000. Its totient is φ = 5074452480.

The previous prime is 21027373429. The next prime is 21027373441. The reversal of 21027373440 is 4437372012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21027373441) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 117471271 + ... + 117471449.

It is an arithmetic number, because the mean of its divisors is an integer number (144068625).

Almost surely, 2^21027373440 is an apocalyptic number.

21027373440 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 21027373440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36881568000).

21027373440 is an abundant number, since it is smaller than the sum of its proper divisors (52735762560).

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

21027373440 is a wasteful number, since it uses less digits than its factorization.

21027373440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338 (or 326 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 33.

The spelling of 21027373440 in words is "twenty-one billion, twenty-seven million, three hundred seventy-three thousand, four hundred forty".