1100120021 has 48 divisors (see below), whose sum is σ = 1519392000. Its totient is φ = 790907040.

The previous prime is 1100120009. The next prime is 1100120039. The reversal of 1100120021 is 1200210011.

It is not a de Polignac number, because 1100120021 - 2⁶ = 1100119957 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1100119990 and 1100120008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1100120621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 538520 + ... + 540558.

It is an arithmetic number, because the mean of its divisors is an integer number (31654000).

Almost surely, 2^1100120021 is an apocalyptic number.

1100120021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1100120021 is a deficient number, since it is larger than the sum of its proper divisors (419271979).

1100120021 is a wasteful number, since it uses less digits than its factorization.

1100120021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2095 (or 2070 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1100120021 is about 33168.0572388556. The cubic root of 1100120021 is about 1032.3176581188.

Adding to 1100120021 its reverse (1200210011), we get a palindrome (2300330032).

It can be divided in two parts, 1100 and 120021, that added together give a palindrome (121121).

The spelling of 1100120021 in words is "one billion, one hundred million, one hundred twenty thousand, twenty-one".