87210805517 has 4 divisors (see below), whose sum is σ = 95139060576. Its totient is φ = 79282550460.

The previous prime is 87210805457. The next prime is 87210805529. The reversal of 87210805517 is 71550801278.

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 87210805517 - 2¹⁰ = 87210804493 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 (87210805217) 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, 3964127513 + ... + 3964127534.

It is an arithmetic number, because the mean of its divisors is an integer number (23784765144).

Almost surely, 2^87210805517 is an apocalyptic number.

It is an amenable number.

87210805517 is a deficient number, since it is larger than the sum of its proper divisors (7928255059).

87210805517 is a wasteful number, since it uses less digits than its factorization.

87210805517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7928255058.

The product of its (nonzero) digits is 156800, while the sum is 44.

The spelling of 87210805517 in words is "eighty-seven billion, two hundred ten million, eight hundred five thousand, five hundred seventeen".