21124203442 has 8 divisors (see below), whose sum is σ = 31917592476. Its totient is φ = 10485005952.

The previous prime is 21124203431. The next prime is 21124203479. The reversal of 21124203442 is 24430242112.

It can be written as a sum of positive squares in 2 ways, for example, as 20260960281 + 863243161 = 142341^2 + 29381^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38547543 + ... + 38548090.

Almost surely, 2^21124203442 is an apocalyptic number.

21124203442 is a deficient number, since it is larger than the sum of its proper divisors (10793389034).

21124203442 is a wasteful number, since it uses less digits than its factorization.

21124203442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77095772.

The product of its (nonzero) digits is 3072, while the sum is 25.

Adding to 21124203442 its reverse (24430242112), we get a palindrome (45554445554).

The spelling of 21124203442 in words is "twenty-one billion, one hundred twenty-four million, two hundred three thousand, four hundred forty-two".