2005140521 has 2 divisors, whose sum is σ = 2005140522. Its totient is φ = 2005140520.

The previous prime is 2005140479. The next prime is 2005140523. The reversal of 2005140521 is 1250415002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1924050496 + 81090025 = 43864^2 + 9005^2 .

It is a cyclic number.

It is not a de Polignac number, because 2005140521 - 2¹⁰ = 2005139497 is a prime.

It is a Sophie Germain prime.

Together with 2005140523, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2005140493 and 2005140502.

It is not a weakly prime, because it can be changed into another prime (2005140523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1002570260 + 1002570261.

It is an arithmetic number, because the mean of its divisors is an integer number (1002570261).

Almost surely, 2^2005140521 is an apocalyptic number.

It is an amenable number.

2005140521 is a deficient number, since it is larger than the sum of its proper divisors (1).

2005140521 is an equidigital number, since it uses as much as digits as its factorization.

2005140521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 2005140521 is about 44778.7954393595. The cubic root of 2005140521 is about 1260.9995681669. Note that the first 3 decimals are identical.

Adding to 2005140521 its reverse (1250415002), we get a palindrome (3255555523).

The spelling of 2005140521 in words is "two billion, five million, one hundred forty thousand, five hundred twenty-one".