21455314304555 has 16 divisors (see below), whose sum is σ = 26636337064800. Its totient is φ = 16571040568320.

The previous prime is 21455314304539. The next prime is 21455314304651. The reversal of 21455314304555 is 55540341355412.

It is not a de Polignac number, because 21455314304555 - 2⁴ = 21455314304539 is a prime.

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, 4181606 + ... + 7771515.

It is an arithmetic number, because the mean of its divisors is an integer number (1664771066550).

Almost surely, 2^{21455314304555} is an apocalyptic number.

21455314304555 is a deficient number, since it is larger than the sum of its proper divisors (5181022760245).

21455314304555 is a wasteful number, since it uses less digits than its factorization.

21455314304555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11965534.

The product of its (nonzero) digits is 3600000, while the sum is 47.

Adding to 21455314304555 its reverse (55540341355412), we get a palindrome (76995655659967).

The spelling of 21455314304555 in words is "twenty-one trillion, four hundred fifty-five billion, three hundred fourteen million, three hundred four thousand, five hundred fifty-five".