21621344066146 has 16 divisors (see below), whose sum is σ = 35389102168800. Its totient is φ = 9825461174880.

The previous prime is 21621344066117. The next prime is 21621344066207. The reversal of 21621344066146 is 64166044312612.

It is a junction number, because it is equal to n+sod(n) for n = 21621344066096 and 21621344066105.

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 7 ways as a sum of consecutive naturals, for example, 121033296 + ... + 121211803.

It is an arithmetic number, because the mean of its divisors is an integer number (2211818885550).

Almost surely, 2^{21621344066146} is an apocalyptic number.

21621344066146 is a deficient number, since it is larger than the sum of its proper divisors (13767758102654).

21621344066146 is a wasteful number, since it uses less digits than its factorization.

21621344066146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242249169.

The product of its (nonzero) digits is 995328, while the sum is 46.

Adding to 21621344066146 its reverse (64166044312612), we get a palindrome (85787388378758).

The spelling of 21621344066146 in words is "twenty-one trillion, six hundred twenty-one billion, three hundred forty-four million, sixty-six thousand, one hundred forty-six".