21453117 has 8 divisors (see below), whose sum is σ = 32690496. Its totient is φ = 12258912.

The previous prime is 21453101. The next prime is 21453119. The reversal of 21453117 is 71135412.

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

It is not a de Polignac number, because 21453117 - 2⁴ = 21453101 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 7 ways as a sum of consecutive naturals, for example, 510768 + ... + 510809.

It is an arithmetic number, because the mean of its divisors is an integer number (4086312).

Almost surely, 2^21453117 is an apocalyptic number.

It is an amenable number.

21453117 is a deficient number, since it is larger than the sum of its proper divisors (11237379).

21453117 is a wasteful number, since it uses less digits than its factorization.

21453117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1021587.

The product of its digits is 840, while the sum is 24.

The square root of 21453117 is about 4631.7509648080. The cubic root of 21453117 is about 277.8626247061.

Adding to 21453117 its reverse (71135412), we get a palindrome (92588529).

The spelling of 21453117 in words is "twenty-one million, four hundred fifty-three thousand, one hundred seventeen".