21252053 has 4 divisors (see below), whose sum is σ = 21419520. Its totient is φ = 21084588.

The previous prime is 21252047. The next prime is 21252059. The reversal of 21252053 is 35025212.

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 an interprime number because it is at equal distance from previous prime (21252047) and next prime (21252059).

It is a cyclic number.

It is not a de Polignac number, because 21252053 - 2²⁴ = 4474837 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 (21252059) 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, 83543 + ... + 83796.

It is an arithmetic number, because the mean of its divisors is an integer number (5354880).

Almost surely, 2^21252053 is an apocalyptic number.

It is an amenable number.

21252053 is a deficient number, since it is larger than the sum of its proper divisors (167467).

21252053 is a wasteful number, since it uses less digits than its factorization.

21252053 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167466.

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 21252053 is about 4609.9949023833. The cubic root of 21252053 is about 276.9918324865.

Adding to 21252053 its reverse (35025212), we get a palindrome (56277265).

The spelling of 21252053 in words is "twenty-one million, two hundred fifty-two thousand, fifty-three".