111212122021121 has 32 divisors (see below), whose sum is σ = 133419448252800. Its totient is φ = 91562365440000.

The previous prime is 111212122021111. The next prime is 111212122021129. The reversal of 111212122021121 is 121120221212111.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 111212122021121 - 2¹⁸ = 111212121758977 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 111212122021093 and 111212122021102.

It is not an unprimeable number, because it can be changed into a prime (111212122021129) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 90223520 + ... + 91447841.

It is an arithmetic number, because the mean of its divisors is an integer number (4169357757900).

Almost surely, 2^{111212122021121} is an apocalyptic number.

111212122021121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

111212122021121 is a deficient number, since it is larger than the sum of its proper divisors (22207326231679).

111212122021121 is a wasteful number, since it uses less digits than its factorization.

111212122021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181671521.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 111212122021121 its reverse (121120221212111), we get a palindrome (232332343233232).

The spelling of 111212122021121 in words is "one hundred eleven trillion, two hundred twelve billion, one hundred twenty-two million, twenty-one thousand, one hundred twenty-one".