2142122021 has 4 divisors (see below), whose sum is σ = 2306900652. Its totient is φ = 1977343392.

The previous prime is 2142121981. The next prime is 2142122053. The reversal of 2142122021 is 1202212412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 450033796 + 1692088225 = 21214^2 + 41135^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2142122021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2142122071) 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 3 ways as a sum of consecutive naturals, for example, 82389296 + ... + 82389321.

It is an arithmetic number, because the mean of its divisors is an integer number (576725163).

Almost surely, 2^2142122021 is an apocalyptic number.

It is an amenable number.

2142122021 is a deficient number, since it is larger than the sum of its proper divisors (164778631).

2142122021 is a wasteful number, since it uses less digits than its factorization.

2142122021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164778630.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 2142122021 is about 46283.0640839606. The cubic root of 2142122021 is about 1289.0845458986.

Adding to 2142122021 its reverse (1202212412), we get a palindrome (3344334433).

The spelling of 2142122021 in words is "two billion, one hundred forty-two million, one hundred twenty-two thousand, twenty-one".