87785817 has 8 divisors (see below), whose sum is σ = 133768896. Its totient is φ = 50163312.

The previous prime is 87785791. The next prime is 87785821. The reversal of 87785817 is 71858778.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 87785817 - 2¹⁸ = 87523673 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 87785817.

It is not an unprimeable number, because it can be changed into a prime (87785837) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2090118 + ... + 2090159.

It is an arithmetic number, because the mean of its divisors is an integer number (16721112).

Almost surely, 2^87785817 is an apocalyptic number.

It is an amenable number.

87785817 is a deficient number, since it is larger than the sum of its proper divisors (45983079).

87785817 is a wasteful number, since it uses less digits than its factorization.

87785817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4180287.

The product of its digits is 878080, while the sum is 51.

The square root of 87785817 is about 9369.4085725834. The cubic root of 87785817 is about 444.4348622772.

The spelling of 87785817 in words is "eighty-seven million, seven hundred eighty-five thousand, eight hundred seventeen".