20400311121 has 4 divisors (see below), whose sum is σ = 27200414832. Its totient is φ = 13600207412.

The previous prime is 20400311111. The next prime is 20400311167. The reversal of 20400311121 is 12111300402.

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 20400311121 - 2⁷ = 20400310993 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20400311121.

It is not an unprimeable number, because it can be changed into a prime (20400311111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3400051851 + ... + 3400051856.

It is an arithmetic number, because the mean of its divisors is an integer number (6800103708).

Almost surely, 2^20400311121 is an apocalyptic number.

It is an amenable number.

20400311121 is a deficient number, since it is larger than the sum of its proper divisors (6800103711).

20400311121 is an equidigital number, since it uses as much as digits as its factorization.

20400311121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6800103710.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 20400311121 its reverse (12111300402), we get a palindrome (32511611523).

The spelling of 20400311121 in words is "twenty billion, four hundred million, three hundred eleven thousand, one hundred twenty-one".