21440434404352 has 88 divisors (see below), whose sum is σ = 44501484576960. Its totient is φ = 10312356741120.

The previous prime is 21440434404341. The next prime is 21440434404421. The reversal of 21440434404352 is 25340443404412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6715518 + ... + 9379714.

Almost surely, 2^{21440434404352} 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 21440434404352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22250742288480).

21440434404352 is an abundant number, since it is smaller than the sum of its proper divisors (23061050172608).

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

21440434404352 is a wasteful number, since it uses less digits than its factorization.

21440434404352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2664517 (or 2664499 counting only the distinct ones).

The product of its (nonzero) digits is 737280, while the sum is 40.

Adding to 21440434404352 its reverse (25340443404412), we get a palindrome (46780877808764).

The spelling of 21440434404352 in words is "twenty-one trillion, four hundred forty billion, four hundred thirty-four million, four hundred four thousand, three hundred fifty-two".