2142212121 has 24 divisors (see below), whose sum is σ = 3571374144. Its totient is φ = 1211997600.

The previous prime is 2142212119. The next prime is 2142212123. The reversal of 2142212121 is 1212122412.

It is an interprime number because it is at equal distance from previous prime (2142212119) and next prime (2142212123).

It is not a de Polignac number, because 2142212121 - 2¹ = 2142212119 is a prime.

2142212121 is a modest number, since divided by 212121 gives 2142 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 2142212094 and 2142212103.

It is not an unprimeable number, because it can be changed into a prime (2142212123) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 161971 + ... + 174696.

It is an arithmetic number, because the mean of its divisors is an integer number (148807256).

Almost surely, 2^2142212121 is an apocalyptic number.

2142212121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2142212121 is a deficient number, since it is larger than the sum of its proper divisors (1429162023).

2142212121 is a wasteful number, since it uses less digits than its factorization.

2142212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336781 (or 336778 counting only the distinct ones).

The product of its digits is 128, while the sum is 18.

The square root of 2142212121 is about 46284.0374319268. The cubic root of 2142212121 is about 1289.1026190815.

Adding to 2142212121 its reverse (1212122412), we get a palindrome (3354334533).

The spelling of 2142212121 in words is "two billion, one hundred forty-two million, two hundred twelve thousand, one hundred twenty-one".