21230255242 has 16 divisors (see below), whose sum is σ = 36396627840. Its totient is φ = 9098204688.

The previous prime is 21230255239. The next prime is 21230255251. The reversal of 21230255242 is 24255203212.

It is a self number, because there is not a number n which added to its sum of digits gives 21230255242.

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, 425323 + ... + 472609.

It is an arithmetic number, because the mean of its divisors is an integer number (2274789240).

Almost surely, 2^21230255242 is an apocalyptic number.

21230255242 is a deficient number, since it is larger than the sum of its proper divisors (15166372598).

21230255242 is a wasteful number, since it uses less digits than its factorization.

21230255242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79365.

The product of its (nonzero) digits is 9600, while the sum is 28.

Adding to 21230255242 its reverse (24255203212), we get a palindrome (45485458454).

The spelling of 21230255242 in words is "twenty-one billion, two hundred thirty million, two hundred fifty-five thousand, two hundred forty-two".