21347903005440 has 576 divisors, whose sum is σ = 80044413829632. Its totient is φ = 4790963404800.

The previous prime is 21347903005427. The next prime is 21347903005519. The reversal of 21347903005440 is 4450030974312.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21347903005392 and 21347903005401.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 43559199 + ... + 44046561.

It is an arithmetic number, because the mean of its divisors is an integer number (138965996232).

Almost surely, 2^{21347903005440} is an apocalyptic number.

21347903005440 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 21347903005440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40022206914816).

21347903005440 is an abundant number, since it is smaller than the sum of its proper divisors (58696510824192).

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

21347903005440 is a wasteful number, since it uses less digits than its factorization.

21347903005440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 487476 (or 487462 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 42.

Adding to 21347903005440 its reverse (4450030974312), we get a palindrome (25797933979752).

The spelling of 21347903005440 in words is "twenty-one trillion, three hundred forty-seven billion, nine hundred three million, five thousand, four hundred forty".