2142717821 has 16 divisors (see below), whose sum is σ = 2230536000. Its totient is φ = 2056779648.

The previous prime is 2142717817. The next prime is 2142717833. The reversal of 2142717821 is 1287172412.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 2142717821 - 2² = 2142717817 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 (2142713821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2042105 + ... + 2043153.

It is an arithmetic number, because the mean of its divisors is an integer number (139408500).

Almost surely, 2^2142717821 is an apocalyptic number.

It is an amenable number.

2142717821 is a deficient number, since it is larger than the sum of its proper divisors (87818179).

2142717821 is a wasteful number, since it uses less digits than its factorization.

2142717821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1868.

The product of its digits is 12544, while the sum is 35.

The square root of 2142717821 is about 46289.5001161170. The cubic root of 2142717821 is about 1289.2040481756.

The spelling of 2142717821 in words is "two billion, one hundred forty-two million, seven hundred seventeen thousand, eight hundred twenty-one".