21111121445 has 32 divisors (see below), whose sum is σ = 27708566400. Its totient is φ = 15379773696.

The previous prime is 21111121439. The next prime is 21111121453. The reversal of 21111121445 is 54412111112.

It is not a de Polignac number, because 21111121445 - 2⁴ = 21111121429 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21111121445.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 608507 + ... + 642263.

It is an arithmetic number, because the mean of its divisors is an integer number (865892700).

Almost surely, 2^21111121445 is an apocalyptic number.

It is an amenable number.

21111121445 is a deficient number, since it is larger than the sum of its proper divisors (6597444955).

21111121445 is a wasteful number, since it uses less digits than its factorization.

21111121445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34037.

The product of its digits is 320, while the sum is 23.

Adding to 21111121445 its reverse (54412111112), we get a palindrome (75523232557).

The spelling of 21111121445 in words is "twenty-one billion, one hundred eleven million, one hundred twenty-one thousand, four hundred forty-five".