21430053 has 6 divisors (see below), whose sum is σ = 30954534. Its totient is φ = 14286696.

The previous prime is 21430037. The next prime is 21430063. The reversal of 21430053 is 35003412.

It can be written as a sum of positive squares in only one way, i.e., 20958084 + 471969 = 4578^2 + 687^2 .

It is not a de Polignac number, because 21430053 - 2⁴ = 21430037 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21430033) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1190550 + ... + 1190567.

It is an arithmetic number, because the mean of its divisors is an integer number (5159089).

Almost surely, 2^21430053 is an apocalyptic number.

It is an amenable number.

21430053 is a deficient number, since it is larger than the sum of its proper divisors (9524481).

21430053 is a wasteful number, since it uses less digits than its factorization.

21430053 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2381123 (or 2381120 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 21430053 is about 4629.2605241010. The cubic root of 21430053 is about 277.7630133604.

Adding to 21430053 its reverse (35003412), we get a palindrome (56433465).

The spelling of 21430053 in words is "twenty-one million, four hundred thirty thousand, fifty-three".