531090386891 has 2 divisors, whose sum is σ = 531090386892. Its totient is φ = 531090386890.

The previous prime is 531090386873. The next prime is 531090386903. The reversal of 531090386891 is 198683090135.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-531090386891 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (531090386851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 265545193445 + 265545193446.

It is an arithmetic number, because the mean of its divisors is an integer number (265545193446).

Almost surely, 2^531090386891 is an apocalyptic number.

531090386891 is a deficient number, since it is larger than the sum of its proper divisors (1).

531090386891 is an equidigital number, since it uses as much as digits as its factorization.

531090386891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1399680, while the sum is 53.

The spelling of 531090386891 in words is "five hundred thirty-one billion, ninety million, three hundred eighty-six thousand, eight hundred ninety-one".