21541541411555 has 32 divisors (see below), whose sum is σ = 28306042652160. Its totient is φ = 15607674846720.

The previous prime is 21541541411471. The next prime is 21541541411563. The reversal of 21541541411555 is 55511414514512.

It is not a de Polignac number, because 21541541411555 - 2¹⁸ = 21541541149411 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16110827 + ... + 17396603.

It is an arithmetic number, because the mean of its divisors is an integer number (884563832880).

Almost surely, 2^{21541541411555} is an apocalyptic number.

21541541411555 is a deficient number, since it is larger than the sum of its proper divisors (6764501240605).

21541541411555 is a wasteful number, since it uses less digits than its factorization.

21541541411555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1286939.

The product of its digits is 400000, while the sum is 44.

The spelling of 21541541411555 in words is "twenty-one trillion, five hundred forty-one billion, five hundred forty-one million, four hundred eleven thousand, five hundred fifty-five".