87809868709 has 4 divisors (see below), whose sum is σ = 88264842316. Its totient is φ = 87354895104.

The previous prime is 87809868701. The next prime is 87809868767. The reversal of 87809868709 is 90786890878.

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 10342279809 + 77467588900 = 101697^2 + 278330^2 .

It is a cyclic number.

It is not a de Polignac number, because 87809868709 - 2³ = 87809868701 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 (87809868701) 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, 227486514 + ... + 227486899.

It is an arithmetic number, because the mean of its divisors is an integer number (22066210579).

Almost surely, 2^87809868709 is an apocalyptic number.

It is an amenable number.

87809868709 is a deficient number, since it is larger than the sum of its proper divisors (454973607).

87809868709 is a wasteful number, since it uses less digits than its factorization.

87809868709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 454973606.

The product of its (nonzero) digits is 97542144, while the sum is 70.

The spelling of 87809868709 in words is "eighty-seven billion, eight hundred nine million, eight hundred sixty-eight thousand, seven hundred nine".