515506065491 has 2 divisors, whose sum is σ = 515506065492. Its totient is φ = 515506065490.

The previous prime is 515506065443. The next prime is 515506065517. The reversal of 515506065491 is 194560605515.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-515506065491 is a prime.

It is a super-2 number, since 2×515506065491² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (515506061491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 257753032745 + 257753032746.

It is an arithmetic number, because the mean of its divisors is an integer number (257753032746).

Almost surely, 2^515506065491 is an apocalyptic number.

515506065491 is a deficient number, since it is larger than the sum of its proper divisors (1).

515506065491 is an equidigital number, since it uses as much as digits as its factorization.

515506065491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 810000, while the sum is 47.

The spelling of 515506065491 in words is "five hundred fifteen billion, five hundred six million, sixty-five thousand, four hundred ninety-one".