87205771 has 4 divisors (see below), whose sum is σ = 87259752. Its totient is φ = 87151792.

The previous prime is 87205751. The next prime is 87205787. The reversal of 87205771 is 17750278.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 87205771 - 2¹¹ = 87203723 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 87205771.

It is not an unprimeable number, because it can be changed into a prime (87205721) 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, 24490 + ... + 27823.

It is an arithmetic number, because the mean of its divisors is an integer number (21814938).

Almost surely, 2^87205771 is an apocalyptic number.

87205771 is a deficient number, since it is larger than the sum of its proper divisors (53981).

87205771 is a wasteful number, since it uses less digits than its factorization.

87205771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53980.

The product of its (nonzero) digits is 27440, while the sum is 37.

The square root of 87205771 is about 9338.4030219305. The cubic root of 87205771 is about 443.4538285295.

The spelling of 87205771 in words is "eighty-seven million, two hundred five thousand, seven hundred seventy-one".