2121112157 has 2 divisors, whose sum is σ = 2121112158. Its totient is φ = 2121112156.

The previous prime is 2121112093. The next prime is 2121112181. The reversal of 2121112157 is 7512111212.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2114068441 + 7043716 = 45979^2 + 2654^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121112157 - 2⁶ = 2121112093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121112057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060556078 + 1060556079.

It is an arithmetic number, because the mean of its divisors is an integer number (1060556079).

Almost surely, 2^2121112157 is an apocalyptic number.

It is an amenable number.

2121112157 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121112157 is an equidigital number, since it uses as much as digits as its factorization.

2121112157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 280, while the sum is 23.

The square root of 2121112157 is about 46055.5334026217. The cubic root of 2121112157 is about 1284.8562587075.

Adding to 2121112157 its reverse (7512111212), we get a palindrome (9633223369).

The spelling of 2121112157 in words is "two billion, one hundred twenty-one million, one hundred twelve thousand, one hundred fifty-seven".