21530230051 has 16 divisors (see below), whose sum is σ = 23943655008. Its totient is φ = 19194739200.

The previous prime is 21530230049. The next prime is 21530230061. The reversal of 21530230051 is 15003203512.

It is a cyclic number.

It is not a de Polignac number, because 21530230051 - 2¹ = 21530230049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21530230061) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 178521 + ... + 273733.

It is an arithmetic number, because the mean of its divisors is an integer number (1496478438).

Almost surely, 2^21530230051 is an apocalyptic number.

21530230051 is a deficient number, since it is larger than the sum of its proper divisors (2413424957).

21530230051 is a wasteful number, since it uses less digits than its factorization.

21530230051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95622.

The product of its (nonzero) digits is 900, while the sum is 22.

Adding to 21530230051 its reverse (15003203512), we get a palindrome (36533433563).

The spelling of 21530230051 in words is "twenty-one billion, five hundred thirty million, two hundred thirty thousand, fifty-one".