21210301242 has 96 divisors (see below), whose sum is σ = 51602503680. Its totient is φ = 6251333760.

The previous prime is 21210301169. The next prime is 21210301279. The reversal of 21210301242 is 24210301212.

It is a happy number.

21210301242 is a `hidden beast` number, since 2 + 121 + 0 + 301 + 242 = 666.

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

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 849517 + ... + 874127.

It is an arithmetic number, because the mean of its divisors is an integer number (537526080).

Almost surely, 2^21210301242 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21210301242, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25801251840).

21210301242 is an abundant number, since it is smaller than the sum of its proper divisors (30392202438).

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

21210301242 is a wasteful number, since it uses less digits than its factorization.

21210301242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24788 (or 24785 counting only the distinct ones).

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

Adding to 21210301242 its reverse (24210301212), we get a palindrome (45420602454).

The spelling of 21210301242 in words is "twenty-one billion, two hundred ten million, three hundred one thousand, two hundred forty-two".