111211021021 has 4 divisors (see below), whose sum is σ = 114798473344. Its totient is φ = 107623568700.

The previous prime is 111211021013. The next prime is 111211021043. The reversal of 111211021021 is 120120112111.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 120120112111 = 2389 ⋅50280499.

It is a cyclic number.

It is not a de Polignac number, because 111211021021 - 2³ = 111211021013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 111211020992 and 111211021010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111211021091) 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, 1793726115 + ... + 1793726176.

It is an arithmetic number, because the mean of its divisors is an integer number (28699618336).

Almost surely, 2^111211021021 is an apocalyptic number.

It is an amenable number.

111211021021 is a deficient number, since it is larger than the sum of its proper divisors (3587452323).

111211021021 is an equidigital number, since it uses as much as digits as its factorization.

111211021021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3587452322.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 111211021021 its reverse (120120112111), we get a palindrome (231331133132).

The spelling of 111211021021 in words is "one hundred eleven billion, two hundred eleven million, twenty-one thousand, twenty-one".