20323121120021 has 4 divisors (see below), whose sum is σ = 20327938171200. Its totient is φ = 20318304068844.

The previous prime is 20323121120009. The next prime is 20323121120023. The reversal of 20323121120021 is 12002112132302.

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 a cyclic number.

It is not a de Polignac number, because 20323121120021 - 2⁴² = 15925074608917 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20323121119975 and 20323121120002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20323121120023) 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, 2408519261 + ... + 2408527698.

It is an arithmetic number, because the mean of its divisors is an integer number (5081984542800).

Almost surely, 2^{20323121120021} is an apocalyptic number.

It is an amenable number.

20323121120021 is a deficient number, since it is larger than the sum of its proper divisors (4817051179).

20323121120021 is an equidigital number, since it uses as much as digits as its factorization.

20323121120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4817051178.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 20323121120021 its reverse (12002112132302), we get a palindrome (32325233252323).

The spelling of 20323121120021 in words is "twenty trillion, three hundred twenty-three billion, one hundred twenty-one million, one hundred twenty thousand, twenty-one".