21155833105 has 16 divisors (see below), whose sum is σ = 27878329728. Its totient is φ = 15284160000.

The previous prime is 21155833103. The next prime is 21155833177. The reversal of 21155833105 is 50133855112.

It is not a de Polignac number, because 21155833105 - 2¹ = 21155833103 is a prime.

It is a super-2 number, since 2×21155833105² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21155833103) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1265376 + ... + 1281985.

It is an arithmetic number, because the mean of its divisors is an integer number (1742395608).

Almost surely, 2^21155833105 is an apocalyptic number.

It is an amenable number.

21155833105 is a deficient number, since it is larger than the sum of its proper divisors (6722496623).

21155833105 is a wasteful number, since it uses less digits than its factorization.

21155833105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2547528.

The product of its (nonzero) digits is 18000, while the sum is 34.

The spelling of 21155833105 in words is "twenty-one billion, one hundred fifty-five million, eight hundred thirty-three thousand, one hundred five".