21111101 has 8 divisors (see below), whose sum is σ = 23824800. Its totient is φ = 18529840.

The previous prime is 21111073. The next prime is 21111113. The reversal of 21111101 is 10111112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21111101 - 2²² = 16916797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111191) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32771 + ... + 33408.

It is an arithmetic number, because the mean of its divisors is an integer number (2978100).

Almost surely, 2^21111101 is an apocalyptic number.

It is an amenable number.

21111101 is a deficient number, since it is larger than the sum of its proper divisors (2713699).

21111101 is a wasteful number, since it uses less digits than its factorization.

21111101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66219.

The product of its (nonzero) digits is 2, while the sum is 8.

The square root of 21111101 is about 4594.6818170576. The cubic root of 21111101 is about 276.3781006048.

Adding to 21111101 its reverse (10111112), we get a palindrome (31222213).

It can be divided in two parts, 21111 and 101, that added together give a palindrome (21212).

The spelling of 21111101 in words is "twenty-one million, one hundred eleven thousand, one hundred one".