21221333430 has 32 divisors (see below), whose sum is σ = 55561310208. Its totient is φ = 5144565600.

The previous prime is 21221333423. The next prime is 21221333467. The reversal of 21221333430 is 3433312212.

It is a self number, because there is not a number n which added to its sum of digits gives 21221333430.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32153206 + ... + 32153865.

It is an arithmetic number, because the mean of its divisors is an integer number (1736290944).

Almost surely, 2^21221333430 is an apocalyptic number.

21221333430 is an abundant number, since it is smaller than the sum of its proper divisors (34339976778).

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

21221333430 is a wasteful number, since it uses less digits than its factorization.

21221333430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64307092.

The product of its (nonzero) digits is 2592, while the sum is 24.

Adding to 21221333430 its reverse (3433312212), we get a palindrome (24654645642).

The spelling of 21221333430 in words is "twenty-one billion, two hundred twenty-one million, three hundred thirty-three thousand, four hundred thirty".