21231210442 has 16 divisors (see below), whose sum is σ = 34299004320. Its totient is φ = 9798324912.

The previous prime is 21231210437. The next prime is 21231210457. The reversal of 21231210442 is 24401213212.

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, 612409 + ... + 646147.

It is an arithmetic number, because the mean of its divisors is an integer number (2143687770).

Almost surely, 2^21231210442 is an apocalyptic number.

21231210442 is a deficient number, since it is larger than the sum of its proper divisors (13067793878).

21231210442 is a wasteful number, since it uses less digits than its factorization.

21231210442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57957.

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 21231210442 its reverse (24401213212), we get a palindrome (45632423654).

The spelling of 21231210442 in words is "twenty-one billion, two hundred thirty-one million, two hundred ten thousand, four hundred forty-two".