2121000111 has 12 divisors (see below), whose sum is σ = 3106818000. Its totient is φ = 1394084160.

The previous prime is 2121000109. The next prime is 2121000113. The reversal of 2121000111 is 1110001212.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (2121000109) and next prime (2121000113).

It is not a de Polignac number, because 2121000111 - 2¹ = 2121000109 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 2121000093 and 2121000102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121000113) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1658986 + ... + 1660263.

It is an arithmetic number, because the mean of its divisors is an integer number (258901500).

Almost surely, 2^2121000111 is an apocalyptic number.

2121000111 is a deficient number, since it is larger than the sum of its proper divisors (985817889).

2121000111 is a wasteful number, since it uses less digits than its factorization.

2121000111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3319326 (or 3319323 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 2121000111 is about 46054.3169637766. The cubic root of 2121000111 is about 1284.8336344851.

Adding to 2121000111 its reverse (1110001212), we get a palindrome (3231001323).

The spelling of 2121000111 in words is "two billion, one hundred twenty-one million, one hundred eleven", and thus it is an aban number.