2142340021 has 2 divisors, whose sum is σ = 2142340022. Its totient is φ = 2142340020.

The previous prime is 2142340019. The next prime is 2142340027. The reversal of 2142340021 is 1200432412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1205061796 + 937278225 = 34714^2 + 30615^2 .

It is a cyclic number.

It is not a de Polignac number, because 2142340021 - 2¹ = 2142340019 is a prime.

Together with 2142340019, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2142340027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1071170010 + 1071170011.

It is an arithmetic number, because the mean of its divisors is an integer number (1071170011).

Almost surely, 2^2142340021 is an apocalyptic number.

It is an amenable number.

2142340021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2142340021 is an equidigital number, since it uses as much as digits as its factorization.

2142340021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 2142340021 is about 46285.4190971628. The cubic root of 2142340021 is about 1289.1282737062.

Adding to 2142340021 its reverse (1200432412), we get a palindrome (3342772433).

The spelling of 2142340021 in words is "two billion, one hundred forty-two million, three hundred forty thousand, twenty-one".