21432053 has 16 divisors (see below), whose sum is σ = 23559984. Its totient is φ = 19415040.

The previous prime is 21432023. The next prime is 21432077. The reversal of 21432053 is 35023412.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 3775249 + 17656804 = 1943^2 + 4202^2 .

It is a cyclic number.

It is not a de Polignac number, because 21432053 - 2¹⁸ = 21169909 is a prime.

It is a super-3 number, since 3×21432053³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21432013) 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 15 ways as a sum of consecutive naturals, for example, 67451 + ... + 67767.

It is an arithmetic number, because the mean of its divisors is an integer number (1472499).

Almost surely, 2^21432053 is an apocalyptic number.

It is an amenable number.

21432053 is a deficient number, since it is larger than the sum of its proper divisors (2127931).

21432053 is a wasteful number, since it uses less digits than its factorization.

21432053 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472.

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 21432053 is about 4629.4765362836. The cubic root of 21432053 is about 277.7716540102.

Adding to 21432053 its reverse (35023412), we get a palindrome (56455465).

The spelling of 21432053 in words is "twenty-one million, four hundred thirty-two thousand, fifty-three".