21432453 has 12 divisors (see below), whose sum is σ = 33242400. Its totient is φ = 12247032.

The previous prime is 21432443. The next prime is 21432473. The reversal of 21432453 is 35423412.

It is not a de Polignac number, because 21432453 - 2⁸ = 21432197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21432403) 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, 72753 + ... + 73046.

It is an arithmetic number, because the mean of its divisors is an integer number (2770200).

Almost surely, 2^21432453 is an apocalyptic number.

It is an amenable number.

21432453 is a deficient number, since it is larger than the sum of its proper divisors (11809947).

21432453 is a wasteful number, since it uses less digits than its factorization.

21432453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145816 (or 145809 counting only the distinct ones).

The product of its digits is 2880, while the sum is 24.

The square root of 21432453 is about 4629.5197375106. The cubic root of 21432453 is about 277.7733820756.

Adding to 21432453 its reverse (35423412), we get a palindrome (56855865).

The spelling of 21432453 in words is "twenty-one million, four hundred thirty-two thousand, four hundred fifty-three".