21330431404517 has 16 divisors (see below), whose sum is σ = 21553327273920. Its totient is φ = 21108767702400.

The previous prime is 21330431404507. The next prime is 21330431404549. The reversal of 21330431404517 is 71540413403312.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21330431404517 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21330431404507) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63085334 + ... + 63422552.

It is an arithmetic number, because the mean of its divisors is an integer number (1347082954620).

Almost surely, 2^{21330431404517} is an apocalyptic number.

It is an amenable number.

21330431404517 is a deficient number, since it is larger than the sum of its proper divisors (222895869403).

21330431404517 is a wasteful number, since it uses less digits than its factorization.

21330431404517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339044.

The product of its (nonzero) digits is 120960, while the sum is 38.

Adding to 21330431404517 its reverse (71540413403312), we get a palindrome (92870844807829).

The spelling of 21330431404517 in words is "twenty-one trillion, three hundred thirty billion, four hundred thirty-one million, four hundred four thousand, five hundred seventeen".