1021100111111 has 4 divisors (see below), whose sum is σ = 1056310459800. Its totient is φ = 985889762424.

The previous prime is 1021100111081. The next prime is 1021100111167. The reversal of 1021100111111 is 1111110011201.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1021100111111 - 2⁶ = 1021100111047 is a prime.

It is a super-4 number, since 4×1021100111111⁴ (a number of 49 digits) contains 4444 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1021100111092 and 1021100111101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021100110111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17605174301 + ... + 17605174358.

It is an arithmetic number, because the mean of its divisors is an integer number (264077614950).

Almost surely, 2^{1021100111111} is an apocalyptic number.

1021100111111 is a deficient number, since it is larger than the sum of its proper divisors (35210348689).

1021100111111 is an equidigital number, since it uses as much as digits as its factorization.

1021100111111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35210348688.

The product of its (nonzero) digits is 2, while the sum is 11.

Adding to 1021100111111 its reverse (1111110011201), we get a palindrome (2132210122312).

The spelling of 1021100111111 in words is "one trillion, twenty-one billion, one hundred million, one hundred eleven thousand, one hundred eleven".