20401122406021 has 4 divisors (see below), whose sum is σ = 23315568464032. Its totient is φ = 17486676348012.

The previous prime is 20401122405959. The next prime is 20401122406073. The reversal of 20401122406021 is 12060422110402.

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 a de Polignac number, because none of the positive numbers 2^k-20401122406021 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 (20401122406321) 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, 1457223028995 + ... + 1457223029008.

It is an arithmetic number, because the mean of its divisors is an integer number (5828892116008).

Almost surely, 2^{20401122406021} is an apocalyptic number.

It is an amenable number.

20401122406021 is a deficient number, since it is larger than the sum of its proper divisors (2914446058011).

20401122406021 is an equidigital number, since it uses as much as digits as its factorization.

20401122406021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2914446058010.

The product of its (nonzero) digits is 1536, while the sum is 25.

Adding to 20401122406021 its reverse (12060422110402), we get a palindrome (32461544516423).

The spelling of 20401122406021 in words is "twenty trillion, four hundred one billion, one hundred twenty-two million, four hundred six thousand, twenty-one".