511481909 has 2 divisors, whose sum is σ = 511481910. Its totient is φ = 511481908.

The previous prime is 511481899. The next prime is 511481911. The reversal of 511481909 is 909184115.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 259371025 + 252110884 = 16105^2 + 15878^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-511481909 is a prime.

It is a super-2 number, since 2×511481909² = 523227486468568562, which contains 22 as substring.

Together with 511481911, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (511481609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 255740954 + 255740955.

It is an arithmetic number, because the mean of its divisors is an integer number (255740955).

Almost surely, 2^511481909 is an apocalyptic number.

It is an amenable number.

511481909 is a deficient number, since it is larger than the sum of its proper divisors (1).

511481909 is an equidigital number, since it uses as much as digits as its factorization.

511481909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 38.

The square root of 511481909 is about 22615.9657985238. The cubic root of 511481909 is about 799.7300698699.

The spelling of 511481909 in words is "five hundred eleven million, four hundred eighty-one thousand, nine hundred nine".