503155535252561 has 4 divisors (see below), whose sum is σ = 503207040588900. Its totient is φ = 503104029916224.

The previous prime is 503155535252521. The next prime is 503155535252599. The reversal of 503155535252561 is 165252535551305.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 63925525678336 + 439230009574225 = 7995344^2 + 20957815^2 .

It is a cyclic number.

It is not a de Polignac number, because 503155535252561 - 2³⁸ = 502880657345617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (503155535252521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25752653516 + ... + 25752673053.

It is an arithmetic number, because the mean of its divisors is an integer number (125801760147225).

Almost surely, 2^{503155535252561} is an apocalyptic number.

It is an amenable number.

503155535252561 is a deficient number, since it is larger than the sum of its proper divisors (51505336339).

503155535252561 is an equidigital number, since it uses as much as digits as its factorization.

503155535252561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51505336338.

The product of its (nonzero) digits is 16875000, while the sum is 53.

The spelling of 503155535252561 in words is "five hundred three trillion, one hundred fifty-five billion, five hundred thirty-five million, two hundred fifty-two thousand, five hundred sixty-one".