855609887 has 4 divisors (see below), whose sum is σ = 933392616. Its totient is φ = 777827160.

The previous prime is 855609883. The next prime is 855609893. The reversal of 855609887 is 788906558.

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

It is not a de Polignac number, because 855609887 - 2² = 855609883 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 (855609883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38891348 + ... + 38891369.

It is an arithmetic number, because the mean of its divisors is an integer number (233348154).

Almost surely, 2^855609887 is an apocalyptic number.

855609887 is a deficient number, since it is larger than the sum of its proper divisors (77782729).

855609887 is a wasteful number, since it uses less digits than its factorization.

855609887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77782728.

The product of its (nonzero) digits is 4838400, while the sum is 56.

The square root of 855609887 is about 29250.8100229720. The cubic root of 855609887 is about 949.3476174734.

The spelling of 855609887 in words is "eight hundred fifty-five million, six hundred nine thousand, eight hundred eighty-seven".