21113111441 has 16 divisors (see below), whose sum is σ = 23114615808. Its totient is φ = 19223265600.

The previous prime is 21113111423. The next prime is 21113111443. The reversal of 21113111441 is 14411131112.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21113111441 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21113111443) 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, 199226 + ... + 286211.

It is an arithmetic number, because the mean of its divisors is an integer number (1444663488).

Almost surely, 2^21113111441 is an apocalyptic number.

It is an amenable number.

21113111441 is a deficient number, since it is larger than the sum of its proper divisors (2001504367).

21113111441 is a wasteful number, since it uses less digits than its factorization.

21113111441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485552.

The product of its digits is 96, while the sum is 20.

Adding to 21113111441 its reverse (14411131112), we get a palindrome (35524242553).

The spelling of 21113111441 in words is "twenty-one billion, one hundred thirteen million, one hundred eleven thousand, four hundred forty-one".