21503432330 has 8 divisors (see below), whose sum is σ = 38706178212. Its totient is φ = 8601372928.

The previous prime is 21503432287. The next prime is 21503432333. The reversal of 21503432330 is 3323430512.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 17277262249 + 4226170081 = 131443^2 + 65009^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21503432330.

It is not an unprimeable number, because it can be changed into a prime (21503432333) 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, 1075171607 + ... + 1075171626.

Almost surely, 2^21503432330 is an apocalyptic number.

21503432330 is a deficient number, since it is larger than the sum of its proper divisors (17202745882).

21503432330 is a wasteful number, since it uses less digits than its factorization.

21503432330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2150343240.

The product of its (nonzero) digits is 6480, while the sum is 26.

Adding to 21503432330 its reverse (3323430512), we get a palindrome (24826862842).

The spelling of 21503432330 in words is "twenty-one billion, five hundred three million, four hundred thirty-two thousand, three hundred thirty".