21211344330 has 64 divisors (see below), whose sum is σ = 55814400000. Its totient is φ = 5116288320.

The previous prime is 21211344299. The next prime is 21211344331. The reversal of 21211344330 is 3344311212.

It is a happy number.

It is a super-2 number, since 2×21211344330² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21211344330.

It is not an unprimeable number, because it can be changed into a prime (21211344331) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 95830 + ... + 227169.

It is an arithmetic number, because the mean of its divisors is an integer number (872100000).

Almost surely, 2^21211344330 is an apocalyptic number.

21211344330 is an abundant number, since it is smaller than the sum of its proper divisors (34603055670).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21211344330 is a wasteful number, since it uses less digits than its factorization.

21211344330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323219.

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 21211344330 its reverse (3344311212), we get a palindrome (24555655542).

The spelling of 21211344330 in words is "twenty-one billion, two hundred eleven million, three hundred forty-four thousand, three hundred thirty".