20201121121989 has 4 divisors (see below), whose sum is σ = 26934828162656. Its totient is φ = 13467414081324.

The previous prime is 20201121121963. The next prime is 20201121121997. The reversal of 20201121121989 is 98912112110202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 20201121121989 - 2⁷ = 20201121121861 is a prime.

It is a super-2 number, since 2×20201121121989² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20201121121589) 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, 3366853520329 + ... + 3366853520334.

It is an arithmetic number, because the mean of its divisors is an integer number (6733707040664).

Almost surely, 2^{20201121121989} is an apocalyptic number.

It is an amenable number.

20201121121989 is a deficient number, since it is larger than the sum of its proper divisors (6733707040667).

20201121121989 is an equidigital number, since it uses as much as digits as its factorization.

20201121121989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6733707040666.

The product of its (nonzero) digits is 10368, while the sum is 39.

The spelling of 20201121121989 in words is "twenty trillion, two hundred one billion, one hundred twenty-one million, one hundred twenty-one thousand, nine hundred eighty-nine".