111101001020021 has 2 divisors, whose sum is σ = 111101001020022. Its totient is φ = 111101001020020.

The previous prime is 111101001020017. The next prime is 111101001020033. The reversal of 111101001020021 is 120020100101111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71369548802500 + 39731452217521 = 8448050^2 + 6303289^2 .

It is a cyclic number.

It is not a de Polignac number, because 111101001020021 - 2² = 111101001020017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111101001019984 and 111101001020011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111101001020071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55550500510010 + 55550500510011.

It is an arithmetic number, because the mean of its divisors is an integer number (55550500510011).

Almost surely, 2^{111101001020021} is an apocalyptic number.

It is an amenable number.

111101001020021 is a deficient number, since it is larger than the sum of its proper divisors (1).

111101001020021 is an equidigital number, since it uses as much as digits as its factorization.

111101001020021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 111101001020021 its reverse (120020100101111), we get a palindrome (231121101121132).

The spelling of 111101001020021 in words is "one hundred eleven trillion, one hundred one billion, one million, twenty thousand, twenty-one".