2111111820 has 72 divisors (see below), whose sum is σ = 6491468256. Its totient is φ = 555247872.

The previous prime is 2111111791. The next prime is 2111111837. The reversal of 2111111820 is 281111112.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 2111111793 and 2111111802.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 67192 + ... + 93471.

Almost surely, 2^2111111820 is an apocalyptic number.

2111111820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2111111820 is an abundant number, since it is smaller than the sum of its proper divisors (4380356436).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2111111820 is a wasteful number, since it uses less digits than its factorization.

2111111820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160751 (or 160746 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

The square root of 2111111820 is about 45946.8368878642. The cubic root of 2111111820 is about 1282.8338540129.

Adding to 2111111820 its reverse (281111112), we get a palindrome (2392222932).

The spelling of 2111111820 in words is "two billion, one hundred eleven million, one hundred eleven thousand, eight hundred twenty".