2331421721 has 2 divisors, whose sum is σ = 2331421722. Its totient is φ = 2331421720.

The previous prime is 2331421711. The next prime is 2331421727. The reversal of 2331421721 is 1271241332.

2331421721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1763076121 + 568345600 = 41989^2 + 23840^2 .

It is a cyclic number.

It is not a de Polignac number, because 2331421721 - 2²² = 2327227417 is a prime.

It is not a weakly prime, because it can be changed into another prime (2331421727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1165710860 + 1165710861.

It is an arithmetic number, because the mean of its divisors is an integer number (1165710861).

Almost surely, 2^2331421721 is an apocalyptic number.

It is an amenable number.

2331421721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2331421721 is an equidigital number, since it uses as much as digits as its factorization.

2331421721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2016, while the sum is 26.

The square root of 2331421721 is about 48284.7980320929. The cubic root of 2331421721 is about 1325.9900934418.

The spelling of 2331421721 in words is "two billion, three hundred thirty-one million, four hundred twenty-one thousand, seven hundred twenty-one".