25506356261613 has 4 divisors (see below), whose sum is σ = 34008475015488. Its totient is φ = 17004237507740.

The previous prime is 25506356261611. The next prime is 25506356261647. The reversal of 25506356261613 is 31616265360552.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25506356261613 - 2¹ = 25506356261611 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25506356261611) 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, 4251059376933 + ... + 4251059376938.

It is an arithmetic number, because the mean of its divisors is an integer number (8502118753872).

Almost surely, 2^{25506356261613} is an apocalyptic number.

It is an amenable number.

25506356261613 is a deficient number, since it is larger than the sum of its proper divisors (8502118753875).

25506356261613 is an equidigital number, since it uses as much as digits as its factorization.

25506356261613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8502118753874.

The product of its (nonzero) digits is 5832000, while the sum is 51.

The spelling of 25506356261613 in words is "twenty-five trillion, five hundred six billion, three hundred fifty-six million, two hundred sixty-one thousand, six hundred thirteen".