2520606721 has 2 divisors, whose sum is σ = 2520606722. Its totient is φ = 2520606720.

The previous prime is 2520606703. The next prime is 2520606787. The reversal of 2520606721 is 1276060252.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1980695025 + 539911696 = 44505^2 + 23236^2 .

It is a cyclic number.

It is not a de Polignac number, because 2520606721 - 2³¹ = 373123073 is a prime.

It is not a weakly prime, because it can be changed into another prime (2520603721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1260303360 + 1260303361.

It is an arithmetic number, because the mean of its divisors is an integer number (1260303361).

Almost surely, 2^2520606721 is an apocalyptic number.

It is an amenable number.

2520606721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2520606721 is an equidigital number, since it uses as much as digits as its factorization.

2520606721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 2520606721 is about 50205.6443141605. The cubic root of 2520606721 is about 1360.9276256857.

Adding to 2520606721 its reverse (1276060252), we get a palindrome (3796666973).

The spelling of 2520606721 in words is "two billion, five hundred twenty million, six hundred six thousand, seven hundred twenty-one".