21453053 has 4 divisors (see below), whose sum is σ = 21649980. Its totient is φ = 21256128.

The previous prime is 21453037. The next prime is 21453059. The reversal of 21453053 is 35035412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17623204 + 3829849 = 4198^2 + 1957^2 .

It is a cyclic number.

It is not a de Polignac number, because 21453053 - 2⁴ = 21453037 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 (21453059) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98300 + ... + 98517.

It is an arithmetic number, because the mean of its divisors is an integer number (5412495).

Almost surely, 2^21453053 is an apocalyptic number.

It is an amenable number.

21453053 is a deficient number, since it is larger than the sum of its proper divisors (196927).

21453053 is a wasteful number, since it uses less digits than its factorization.

21453053 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196926.

The product of its (nonzero) digits is 1800, while the sum is 23.

The square root of 21453053 is about 4631.7440559686. The cubic root of 21453053 is about 277.8623483947.

Adding to 21453053 its reverse (35035412), we get a palindrome (56488465).

The spelling of 21453053 in words is "twenty-one million, four hundred fifty-three thousand, fifty-three".