2506985194561 has 4 divisors (see below), whose sum is σ = 2507014818900. Its totient is φ = 2506955570224.

The previous prime is 2506985194543. The next prime is 2506985194589. The reversal of 2506985194561 is 1654915896052.

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 1630831161600 + 876154032961 = 1277040^2 + 936031^2 .

It is a cyclic number.

It is not a de Polignac number, because 2506985194561 - 2⁵ = 2506985194529 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2506985194561.

It is not an unprimeable number, because it can be changed into a prime (2506985194501) 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, 14684866 + ... + 14854603.

It is an arithmetic number, because the mean of its divisors is an integer number (626753704725).

Almost surely, 2^{2506985194561} is an apocalyptic number.

It is an amenable number.

2506985194561 is a deficient number, since it is larger than the sum of its proper divisors (29624339).

2506985194561 is an equidigital number, since it uses as much as digits as its factorization.

2506985194561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29624338.

The product of its (nonzero) digits is 23328000, while the sum is 61.

The spelling of 2506985194561 in words is "two trillion, five hundred six billion, nine hundred eighty-five million, one hundred ninety-four thousand, five hundred sixty-one".