21621343236306 has 32 divisors (see below), whose sum is σ = 47252332120896. Its totient is φ = 6541020480000.

The previous prime is 21621343236263. The next prime is 21621343236331. The reversal of 21621343236306 is 60363234312612.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 272502855 + ... + 272582186.

It is an arithmetic number, because the mean of its divisors is an integer number (1476635378778).

Almost surely, 2^{21621343236306} is an apocalyptic number.

21621343236306 is an abundant number, since it is smaller than the sum of its proper divisors (25630988884590).

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

21621343236306 is a wasteful number, since it uses less digits than its factorization.

21621343236306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 545085658.

The product of its (nonzero) digits is 559872, while the sum is 42.

Adding to 21621343236306 its reverse (60363234312612), we get a palindrome (81984577548918).

The spelling of 21621343236306 in words is "twenty-one trillion, six hundred twenty-one billion, three hundred forty-three million, two hundred thirty-six thousand, three hundred six".