21220230234 has 16 divisors (see below), whose sum is σ = 48503383488. Its totient is φ = 6062922912.

The previous prime is 21220230181. The next prime is 21220230257. The reversal of 21220230234 is 43203202212.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 21220230234.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252621747 + ... + 252621830.

It is an arithmetic number, because the mean of its divisors is an integer number (3031461468).

Almost surely, 2^21220230234 is an apocalyptic number.

21220230234 is an abundant number, since it is smaller than the sum of its proper divisors (27283153254).

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

21220230234 is a wasteful number, since it uses less digits than its factorization.

21220230234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 505243589.

The product of its (nonzero) digits is 1152, while the sum is 21.

Adding to 21220230234 its reverse (43203202212), we get a palindrome (64423432446).

The spelling of 21220230234 in words is "twenty-one billion, two hundred twenty million, two hundred thirty thousand, two hundred thirty-four".