217056887 has 4 divisors (see below), whose sum is σ = 217134216. Its totient is φ = 216979560.

The previous prime is 217056859. The next prime is 217056899. The reversal of 217056887 is 788650712.

217056887 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 217056887 - 2¹⁰ = 217055863 is a prime.

It is a super-2 number, since 2×217056887² = 94227384388261538, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217056487) 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, 34289 + ... + 40122.

It is an arithmetic number, because the mean of its divisors is an integer number (54283554).

Almost surely, 2^217056887 is an apocalyptic number.

217056887 is a deficient number, since it is larger than the sum of its proper divisors (77329).

217056887 is an equidigital number, since it uses as much as digits as its factorization.

217056887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77328.

The product of its (nonzero) digits is 188160, while the sum is 44.

The square root of 217056887 is about 14732.8506067224. The cubic root of 217056887 is about 600.9770073051.

The spelling of 217056887 in words is "two hundred seventeen million, fifty-six thousand, eight hundred eighty-seven".