21354111 has 12 divisors (see below), whose sum is σ = 31987592. Its totient is φ = 14235912.

The previous prime is 21354107. The next prime is 21354139. The reversal of 21354111 is 11145312.

It is not a de Polignac number, because 21354111 - 2² = 21354107 is a prime.

It is a Duffinian number.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21354181) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43696 + ... + 44181.

Almost surely, 2^21354111 is an apocalyptic number.

21354111 is a deficient number, since it is larger than the sum of its proper divisors (10633481).

21354111 is an frugal number, since it uses more digits than its factorization.

21354111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87892 (or 87880 counting only the distinct ones).

The product of its digits is 120, while the sum is 18.

The square root of 21354111 is about 4621.0508545135. The cubic root of 21354111 is about 277.4345207084.

Adding to 21354111 its reverse (11145312), we get a palindrome (32499423).

The spelling of 21354111 in words is "twenty-one million, three hundred fifty-four thousand, one hundred eleven".