25515151565 has 4 divisors (see below), whose sum is σ = 30618181884. Its totient is φ = 20412121248.

The previous prime is 25515151561. The next prime is 25515151583. The reversal of 25515151565 is 56515151552.

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 14729705956 + 10785445609 = 121366^2 + 103853^2 .

It is a cyclic number.

It is not a de Polignac number, because 25515151565 - 2² = 25515151561 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25515151561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2551515152 + ... + 2551515161.

It is an arithmetic number, because the mean of its divisors is an integer number (7654545471).

Almost surely, 2^25515151565 is an apocalyptic number.

It is an amenable number.

25515151565 is a deficient number, since it is larger than the sum of its proper divisors (5103030319).

25515151565 is an equidigital number, since it uses as much as digits as its factorization.

25515151565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5103030318.

The product of its digits is 187500, while the sum is 41.

The spelling of 25515151565 in words is "twenty-five billion, five hundred fifteen million, one hundred fifty-one thousand, five hundred sixty-five".