515243101235561 has 2 divisors, whose sum is σ = 515243101235562. Its totient is φ = 515243101235560.

The previous prime is 515243101235431. The next prime is 515243101235581. The reversal of 515243101235561 is 165532101342515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 430707139645225 + 84535961590336 = 20753485^2 + 9194344^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-515243101235561 is a prime.

It is a super-2 number, since 2×515243101235561² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (515243101235581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 257621550617780 + 257621550617781.

It is an arithmetic number, because the mean of its divisors is an integer number (257621550617781).

Almost surely, 2^{515243101235561} is an apocalyptic number.

It is an amenable number.

515243101235561 is a deficient number, since it is larger than the sum of its proper divisors (1).

515243101235561 is an equidigital number, since it uses as much as digits as its factorization.

515243101235561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 540000, while the sum is 44.

The spelling of 515243101235561 in words is "five hundred fifteen trillion, two hundred forty-three billion, one hundred one million, two hundred thirty-five thousand, five hundred sixty-one".