87720175889 has 4 divisors (see below), whose sum is σ = 88000432356. Its totient is φ = 87439919424.

The previous prime is 87720175877. The next prime is 87720175891. The reversal of 87720175889 is 98857102778.

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 26616291025 + 61103884864 = 163145^2 + 247192^2 .

It is a cyclic number.

It is not a de Polignac number, because 87720175889 - 2⁸ = 87720175633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87720177889) 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, 140127764 + ... + 140128389.

It is an arithmetic number, because the mean of its divisors is an integer number (22000108089).

Almost surely, 2^87720175889 is an apocalyptic number.

It is an amenable number.

87720175889 is a deficient number, since it is larger than the sum of its proper divisors (280256467).

87720175889 is a wasteful number, since it uses less digits than its factorization.

87720175889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280256466.

The product of its (nonzero) digits is 15805440, while the sum is 62.

The spelling of 87720175889 in words is "eighty-seven billion, seven hundred twenty million, one hundred seventy-five thousand, eight hundred eighty-nine".