2645520509 has 2 divisors, whose sum is σ = 2645520510. Its totient is φ = 2645520508.

The previous prime is 2645520497. The next prime is 2645520523. The reversal of 2645520509 is 9050255462.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2564916025 + 80604484 = 50645^2 + 8978^2 .

It is a cyclic number.

It is not a de Polignac number, because 2645520509 - 2²⁰ = 2644471933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2645523509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1322760254 + 1322760255.

It is an arithmetic number, because the mean of its divisors is an integer number (1322760255).

Almost surely, 2^2645520509 is an apocalyptic number.

It is an amenable number.

2645520509 is a deficient number, since it is larger than the sum of its proper divisors (1).

2645520509 is an equidigital number, since it uses as much as digits as its factorization.

2645520509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108000, while the sum is 38.

The square root of 2645520509 is about 51434.6236401123. The cubic root of 2645520509 is about 1383.0473352269.

It can be divided in two parts, 26455 and 20509, that added together give a palindrome (46964).

The spelling of 2645520509 in words is "two billion, six hundred forty-five million, five hundred twenty thousand, five hundred nine".