21121660052 has 12 divisors (see below), whose sum is σ = 37003132320. Its totient is φ = 10549336536.

The previous prime is 21121660051. The next prime is 21121660111. The reversal of 21121660052 is 25006612112.

It is a super-2 number, since 2×21121660052² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121660051) 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 3 ways as a sum of consecutive naturals, for example, 2869238 + ... + 2876589.

It is an arithmetic number, because the mean of its divisors is an integer number (3083594360).

Almost surely, 2^21121660052 is an apocalyptic number.

It is an amenable number.

21121660052 is a deficient number, since it is larger than the sum of its proper divisors (15881472268).

21121660052 is a wasteful number, since it uses less digits than its factorization.

21121660052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5746750 (or 5746748 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The spelling of 21121660052 in words is "twenty-one billion, one hundred twenty-one million, six hundred sixty thousand, fifty-two".