21111121316 has 24 divisors (see below), whose sum is σ = 37644866616. Its totient is φ = 10356318720.

The previous prime is 21111121301. The next prime is 21111121333. The reversal of 21111121316 is 61312111112.

It can be written as a sum of positive squares in 4 ways, for example, as 285745216 + 20825376100 = 16904^2 + 144310^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12101 + ... + 205836.

It is an arithmetic number, because the mean of its divisors is an integer number (1568536109).

Almost surely, 2^21111121316 is an apocalyptic number.

It is an amenable number.

21111121316 is a deficient number, since it is larger than the sum of its proper divisors (16533745300).

21111121316 is a wasteful number, since it uses less digits than its factorization.

21111121316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218399 (or 218397 counting only the distinct ones).

The product of its digits is 72, while the sum is 20.

Adding to 21111121316 its reverse (61312111112), we get a palindrome (82423232428).

The spelling of 21111121316 in words is "twenty-one billion, one hundred eleven million, one hundred twenty-one thousand, three hundred sixteen".