20202121243 has 4 divisors (see below), whose sum is σ = 20349582120. Its totient is φ = 20054660368.

The previous prime is 20202121229. The next prime is 20202121271. The reversal of 20202121243 is 34212120202.

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

It is a cyclic number.

It is not a de Polignac number, because 20202121243 - 2²⁹ = 19665250331 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20202121243.

It is not an unprimeable number, because it can be changed into a prime (20202121273) 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, 73730233 + ... + 73730506.

It is an arithmetic number, because the mean of its divisors is an integer number (5087395530).

Almost surely, 2^20202121243 is an apocalyptic number.

20202121243 is a deficient number, since it is larger than the sum of its proper divisors (147460877).

20202121243 is a wasteful number, since it uses less digits than its factorization.

20202121243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147460876.

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

Adding to 20202121243 its reverse (34212120202), we get a palindrome (54414241445).

The spelling of 20202121243 in words is "twenty billion, two hundred two million, one hundred twenty-one thousand, two hundred forty-three".