21115514135361 has 16 divisors (see below), whose sum is σ = 28192584340800. Its totient is φ = 14057731327488.

The previous prime is 21115514135323. The next prime is 21115514135461. The reversal of 21115514135361 is 16353141551112.

It is not a de Polignac number, because 21115514135361 - 2⁶ = 21115514135297 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21115514135461) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 17715130 + ... + 18869468.

It is an arithmetic number, because the mean of its divisors is an integer number (1762036521300).

Almost surely, 2^{21115514135361} is an apocalyptic number.

It is an amenable number.

21115514135361 is a deficient number, since it is larger than the sum of its proper divisors (7077070205439).

21115514135361 is a wasteful number, since it uses less digits than its factorization.

21115514135361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1162688.

The product of its digits is 54000, while the sum is 39.

Adding to 21115514135361 its reverse (16353141551112), we get a palindrome (37468655686473).

The spelling of 21115514135361 in words is "twenty-one trillion, one hundred fifteen billion, five hundred fourteen million, one hundred thirty-five thousand, three hundred sixty-one".