111111021021 has 192 divisors, whose sum is σ = 213348377088. Its totient is φ = 49876992000.

The previous prime is 111111021017. The next prime is 111111021079. The reversal of 111111021021 is 120120111111.

It is not a de Polignac number, because 111111021021 - 2² = 111111021017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111111020988 and 111111021006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111111023021) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 135335791 + ... + 135336611.

It is an arithmetic number, because the mean of its divisors is an integer number (1111189464).

Almost surely, 2^111111021021 is an apocalyptic number.

111111021021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

111111021021 is a deficient number, since it is larger than the sum of its proper divisors (102237356067).

111111021021 is a wasteful number, since it uses less digits than its factorization.

111111021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1124 (or 1113 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 12.

Adding to 111111021021 its reverse (120120111111), we get a palindrome (231231132132).

The spelling of 111111021021 in words is "one hundred eleven billion, one hundred eleven million, twenty-one thousand, twenty-one".