21155833155 has 16 divisors (see below), whose sum is σ = 33974244864. Its totient is φ = 11241473760.

The previous prime is 21155833103. The next prime is 21155833177. The reversal of 21155833155 is 55133855112.

It is not a de Polignac number, because 21155833155 - 2⁶ = 21155833091 is a prime.

It is an unprimeable number.

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, 2598129 + ... + 2606258.

It is an arithmetic number, because the mean of its divisors is an integer number (2123390304).

Almost surely, 2^21155833155 is an apocalyptic number.

21155833155 is a deficient number, since it is larger than the sum of its proper divisors (12818411709).

21155833155 is a wasteful number, since it uses less digits than its factorization.

21155833155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5204666.

The product of its digits is 90000, while the sum is 39.

The spelling of 21155833155 in words is "twenty-one billion, one hundred fifty-five million, eight hundred thirty-three thousand, one hundred fifty-five".