21945340248 has 128 divisors (see below), whose sum is σ = 60871312320. Its totient is φ = 6549258240.

The previous prime is 21945340247. The next prime is 21945340301. The reversal of 21945340248 is 84204354912.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21945340247) 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, 3887508 + ... + 3893148.

Almost surely, 2^21945340248 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21945340248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30435656160).

21945340248 is an abundant number, since it is smaller than the sum of its proper divisors (38925972072).

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

21945340248 is a wasteful number, since it uses less digits than its factorization.

21945340248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6037 (or 6033 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 42.

The spelling of 21945340248 in words is "twenty-one billion, nine hundred forty-five million, three hundred forty thousand, two hundred forty-eight".