21213301440 has 224 divisors, whose sum is σ = 68938444800. Its totient is φ = 5524992000.

The previous prime is 21213301397. The next prime is 21213301451. The reversal of 21213301440 is 4410331212.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8841361 + ... + 8843759.

Almost surely, 2^21213301440 is an apocalyptic number.

21213301440 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 21213301440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34469222400).

21213301440 is an abundant number, since it is smaller than the sum of its proper divisors (47725143360).

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

21213301440 is a wasteful number, since it uses less digits than its factorization.

21213301440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2631 (or 2621 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21213301440 its reverse (4410331212), we get a palindrome (25623632652).

The spelling of 21213301440 in words is "twenty-one billion, two hundred thirteen million, three hundred one thousand, four hundred forty".