87819647 has 4 divisors (see below), whose sum is σ = 89130456. Its totient is φ = 86508840.

The previous prime is 87819643. The next prime is 87819661. The reversal of 87819647 is 74691878.

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 87819647 - 2² = 87819643 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 87819595 and 87819604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87819643) 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, 655304 + ... + 655437.

It is an arithmetic number, because the mean of its divisors is an integer number (22282614).

Almost surely, 2^87819647 is an apocalyptic number.

87819647 is a deficient number, since it is larger than the sum of its proper divisors (1310809).

87819647 is a wasteful number, since it uses less digits than its factorization.

87819647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1310808.

The product of its digits is 677376, while the sum is 50.

The square root of 87819647 is about 9371.2137420934. The cubic root of 87819647 is about 444.4919455318.

The spelling of 87819647 in words is "eighty-seven million, eight hundred nineteen thousand, six hundred forty-seven".