21115655213315 has 64 divisors (see below), whose sum is σ = 28936588262400. Its totient is φ = 14663188560384.

The previous prime is 21115655213311. The next prime is 21115655213329. The reversal of 21115655213315 is 51331255651112.

It is a happy number.

It is not a de Polignac number, because 21115655213315 - 2² = 21115655213311 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21115655213311) 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 63 ways as a sum of consecutive naturals, for example, 1187397914 + ... + 1187415696.

It is an arithmetic number, because the mean of its divisors is an integer number (452134191600).

Almost surely, 2^{21115655213315} is an apocalyptic number.

21115655213315 is a deficient number, since it is larger than the sum of its proper divisors (7820933049085).

21115655213315 is a wasteful number, since it uses less digits than its factorization.

21115655213315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24876.

The product of its digits is 135000, while the sum is 41.

The spelling of 21115655213315 in words is "twenty-one trillion, one hundred fifteen billion, six hundred fifty-five million, two hundred thirteen thousand, three hundred fifteen".