2540382721 has 2 divisors, whose sum is σ = 2540382722. Its totient is φ = 2540382720.

The previous prime is 2540382679. The next prime is 2540382731. The reversal of 2540382721 is 1272830452.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2119681600 + 420701121 = 46040^2 + 20511^2 .

It is a cyclic number.

It is not a de Polignac number, because 2540382721 - 2¹¹ = 2540380673 is a prime.

It is not a weakly prime, because it can be changed into another prime (2540382731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1270191360 + 1270191361.

It is an arithmetic number, because the mean of its divisors is an integer number (1270191361).

Almost surely, 2^2540382721 is an apocalyptic number.

It is an amenable number.

2540382721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2540382721 is an equidigital number, since it uses as much as digits as its factorization.

2540382721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26880, while the sum is 34.

The square root of 2540382721 is about 50402.2094852994. The cubic root of 2540382721 is about 1364.4775149263.

The spelling of 2540382721 in words is "two billion, five hundred forty million, three hundred eighty-two thousand, seven hundred twenty-one".