20400020111 has 12 divisors (see below), whose sum is σ = 22796705232. Its totient is φ = 18189486144.

The previous prime is 20400020093. The next prime is 20400020129. The reversal of 20400020111 is 11102000402.

It is an interprime number because it is at equal distance from previous prime (20400020093) and next prime (20400020129).

It is a de Polignac number, because none of the positive numbers 2^k-20400020111 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20400020092 and 20400020101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20400020141) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1655915 + ... + 1668188.

It is an arithmetic number, because the mean of its divisors is an integer number (1899725436).

Almost surely, 2^20400020111 is an apocalyptic number.

20400020111 is a deficient number, since it is larger than the sum of its proper divisors (2396685121).

20400020111 is a wasteful number, since it uses less digits than its factorization.

20400020111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3324158 (or 3324139 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 20400020111 its reverse (11102000402), we get a palindrome (31502020513).

The spelling of 20400020111 in words is "twenty billion, four hundred million, twenty thousand, one hundred eleven".