21301210242 has 24 divisors (see below), whose sum is σ = 49702824444. Its totient is φ = 6554218464.

The previous prime is 21301210207. The next prime is 21301210247. The reversal of 21301210242 is 24201210312.

It is a happy number.

21301210242 is a `hidden beast` number, since 213 + 0 + 1 + 210 + 242 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 20729952441 + 571257801 = 143979^2 + 23901^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21301210247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45515173 + ... + 45515640.

Almost surely, 2^21301210242 is an apocalyptic number.

21301210242 is an abundant number, since it is smaller than the sum of its proper divisors (28401614202).

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

21301210242 is a wasteful number, since it uses less digits than its factorization.

21301210242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91030834 (or 91030831 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21301210242 its reverse (24201210312), we get a palindrome (45502420554).

The spelling of 21301210242 in words is "twenty-one billion, three hundred one million, two hundred ten thousand, two hundred forty-two".