509554640891 has 2 divisors, whose sum is σ = 509554640892. Its totient is φ = 509554640890.

The previous prime is 509554640879. The next prime is 509554640939. The reversal of 509554640891 is 198046455905.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-509554640891 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (509554640831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 254777320445 + 254777320446.

It is an arithmetic number, because the mean of its divisors is an integer number (254777320446).

Almost surely, 2^509554640891 is an apocalyptic number.

509554640891 is a deficient number, since it is larger than the sum of its proper divisors (1).

509554640891 is an equidigital number, since it uses as much as digits as its factorization.

509554640891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776000, while the sum is 56.

The spelling of 509554640891 in words is "five hundred nine billion, five hundred fifty-four million, six hundred forty thousand, eight hundred ninety-one".