242123200021 has 4 divisors (see below), whose sum is σ = 243127860844. Its totient is φ = 241118539200.

The previous prime is 242123199863. The next prime is 242123200049. The reversal of 242123200021 is 120002321242.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 75037644900 + 167085555121 = 273930^2 + 408761^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-242123200021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (242123209021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 502330050 + ... + 502330531.

It is an arithmetic number, because the mean of its divisors is an integer number (60781965211).

Almost surely, 2^242123200021 is an apocalyptic number.

It is an amenable number.

242123200021 is a deficient number, since it is larger than the sum of its proper divisors (1004660823).

242123200021 is a wasteful number, since it uses less digits than its factorization.

242123200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1004660822.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 242123200021 its reverse (120002321242), we get a palindrome (362125521263).

The spelling of 242123200021 in words is "two hundred forty-two billion, one hundred twenty-three million, two hundred thousand, twenty-one".