2520605221 has 4 divisors (see below), whose sum is σ = 2521241100. Its totient is φ = 2519969344.

The previous prime is 2520605203. The next prime is 2520605239. The reversal of 2520605221 is 1225060252.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (2520605203) and next prime (2520605239).

It can be written as a sum of positive squares in 2 ways, for example, as 1463445025 + 1057160196 = 38255^2 + 32514^2 .

It is a cyclic number.

It is not a de Polignac number, because 2520605221 - 2²⁹ = 1983734309 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 (2520605281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 311956 + ... + 319933.

It is an arithmetic number, because the mean of its divisors is an integer number (630310275).

Almost surely, 2^2520605221 is an apocalyptic number.

It is an amenable number.

2520605221 is a deficient number, since it is larger than the sum of its proper divisors (635879).

2520605221 is an equidigital number, since it uses as much as digits as its factorization.

2520605221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 635878.

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 2520605221 is about 50205.6293755989. The cubic root of 2520605221 is about 1360.9273557254.

Adding to 2520605221 its reverse (1225060252), we get a palindrome (3745665473).

The spelling of 2520605221 in words is "two billion, five hundred twenty million, six hundred five thousand, two hundred twenty-one".