21453111 has 6 divisors (see below), whose sum is σ = 30987840. Its totient is φ = 14302068.

The previous prime is 21453101. The next prime is 21453119. The reversal of 21453111 is 11135412.

It is not a de Polignac number, because 21453111 - 2⁵ = 21453079 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21453119) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1191831 + ... + 1191848.

It is an arithmetic number, because the mean of its divisors is an integer number (5164640).

Almost surely, 2^21453111 is an apocalyptic number.

21453111 is a deficient number, since it is larger than the sum of its proper divisors (9534729).

21453111 is a wasteful number, since it uses less digits than its factorization.

21453111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2383685 (or 2383682 counting only the distinct ones).

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

The square root of 21453111 is about 4631.7503171048. The cubic root of 21453111 is about 277.8625988020.

Adding to 21453111 its reverse (11135412), we get a palindrome (32588523).

The spelling of 21453111 in words is "twenty-one million, four hundred fifty-three thousand, one hundred eleven".