2133997721 has 2 divisors, whose sum is σ = 2133997722. Its totient is φ = 2133997720.

The previous prime is 2133997693. The next prime is 2133997739. The reversal of 2133997721 is 1277993312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2114988121 + 19009600 = 45989^2 + 4360^2 .

It is a cyclic number.

It is not a de Polignac number, because 2133997721 - 2³⁰ = 1060255897 is a prime.

It is not a weakly prime, because it can be changed into another prime (2133997781) 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 as a sum of consecutive naturals, namely, 1066998860 + 1066998861.

It is an arithmetic number, because the mean of its divisors is an integer number (1066998861).

Almost surely, 2^2133997721 is an apocalyptic number.

It is an amenable number.

2133997721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2133997721 is an equidigital number, since it uses as much as digits as its factorization.

2133997721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 142884, while the sum is 44.

The square root of 2133997721 is about 46195.2131827530. The cubic root of 2133997721 is about 1287.4528029452.

The spelling of 2133997721 in words is "two billion, one hundred thirty-three million, nine hundred ninety-seven thousand, seven hundred twenty-one".