21298453 has 4 divisors (see below), whose sum is σ = 23234688. Its totient is φ = 19362220.

The previous prime is 21298447. The next prime is 21298471. The reversal of 21298453 is 35489212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21298453 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 (21298493) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 968101 + ... + 968122.

It is an arithmetic number, because the mean of its divisors is an integer number (5808672).

Almost surely, 2^21298453 is an apocalyptic number.

It is an amenable number.

21298453 is a deficient number, since it is larger than the sum of its proper divisors (1936235).

21298453 is a wasteful number, since it uses less digits than its factorization.

21298453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1936234.

The product of its digits is 17280, while the sum is 34.

The square root of 21298453 is about 4615.0247019924. The cubic root of 21298453 is about 277.1932730832.

The spelling of 21298453 in words is "twenty-one million, two hundred ninety-eight thousand, four hundred fifty-three".