20021311124243 has 128 divisors (see below), whose sum is σ = 26334915747840. Its totient is φ = 14929754112000.

The previous prime is 20021311124239. The next prime is 20021311124257. The reversal of 20021311124243 is 34242111312002.

It is a happy number.

It is not a de Polignac number, because 20021311124243 - 2² = 20021311124239 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20021311124443) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 5702450858 + ... + 5702454368.

It is an arithmetic number, because the mean of its divisors is an integer number (205741529280).

Almost surely, 2^{20021311124243} is an apocalyptic number.

20021311124243 is a deficient number, since it is larger than the sum of its proper divisors (6313604623597).

20021311124243 is a wasteful number, since it uses less digits than its factorization.

20021311124243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5349.

The product of its (nonzero) digits is 2304, while the sum is 26.

Adding to 20021311124243 its reverse (34242111312002), we get a palindrome (54263422436245).

The spelling of 20021311124243 in words is "twenty trillion, twenty-one billion, three hundred eleven million, one hundred twenty-four thousand, two hundred forty-three".