21530353430 has 64 divisors (see below), whose sum is σ = 40363411968. Its totient is φ = 8259962880.

The previous prime is 21530353423. The next prime is 21530353441. The reversal of 21530353430 is 3435303512.

It is a super-2 number, since 2×21530353430² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21530353393 and 21530353402.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31802252 + ... + 31802928.

It is an arithmetic number, because the mean of its divisors is an integer number (630678312).

Almost surely, 2^21530353430 is an apocalyptic number.

21530353430 is a deficient number, since it is larger than the sum of its proper divisors (18833058538).

21530353430 is a wasteful number, since it uses less digits than its factorization.

21530353430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1481.

The product of its (nonzero) digits is 16200, while the sum is 29.

Adding to 21530353430 its reverse (3435303512), we get a palindrome (24965656942).

The spelling of 21530353430 in words is "twenty-one billion, five hundred thirty million, three hundred fifty-three thousand, four hundred thirty".