21121164228 has 48 divisors (see below), whose sum is σ = 49965552000. Its totient is φ = 6943250688.

The previous prime is 21121164193. The next prime is 21121164257. The reversal of 21121164228 is 82246112112.

It is a super-2 number, since 2×21121164228² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21121164195 and 21121164204.

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, 390033 + ... + 440871.

It is an arithmetic number, because the mean of its divisors is an integer number (1040949000).

Almost surely, 2^21121164228 is an apocalyptic number.

It is an amenable number.

21121164228 is an abundant number, since it is smaller than the sum of its proper divisors (28844387772).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21121164228 is a wasteful number, since it uses less digits than its factorization.

21121164228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51324 (or 51322 counting only the distinct ones).

The product of its digits is 3072, while the sum is 30.

The spelling of 21121164228 in words is "twenty-one billion, one hundred twenty-one million, one hundred sixty-four thousand, two hundred twenty-eight".