87636912109 has 4 divisors (see below), whose sum is σ = 92792024604. Its totient is φ = 82481799616.

The previous prime is 87636912091. The next prime is 87636912119. The reversal of 87636912109 is 90121963678.

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 77202289609 + 10434622500 = 277853^2 + 102150^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-87636912109 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 (87636912119) 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, 2577556222 + ... + 2577556255.

It is an arithmetic number, because the mean of its divisors is an integer number (23198006151).

Almost surely, 2^87636912109 is an apocalyptic number.

It is an amenable number.

87636912109 is a deficient number, since it is larger than the sum of its proper divisors (5155112495).

87636912109 is a wasteful number, since it uses less digits than its factorization.

87636912109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5155112494.

The product of its (nonzero) digits is 979776, while the sum is 52.

The spelling of 87636912109 in words is "eighty-seven billion, six hundred thirty-six million, nine hundred twelve thousand, one hundred nine".