21155142215115 has 32 divisors (see below), whose sum is σ = 37981509480000. Its totient is φ = 11171032185600.

The previous prime is 21155142215101. The next prime is 21155142215161. The reversal of 21155142215115 is 51151224155112.

21155142215115 is a `hidden beast` number, since 2 + 1 + 1 + 5 + 514 + 2 + 21 + 5 + 115 = 666.

It is not a de Polignac number, because 21155142215115 - 2¹⁹ = 21155141690827 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21155142215115.

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, 775752490 + ... + 775779759.

It is an arithmetic number, because the mean of its divisors is an integer number (1186922171250).

Almost surely, 2^{21155142215115} is an apocalyptic number.

21155142215115 is a deficient number, since it is larger than the sum of its proper divisors (16826367264885).

21155142215115 is a wasteful number, since it uses less digits than its factorization.

21155142215115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1551532364 (or 1551532358 counting only the distinct ones).

The product of its digits is 20000, while the sum is 36.

The spelling of 21155142215115 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred forty-two million, two hundred fifteen thousand, one hundred fifteen".