87949865 has 4 divisors (see below), whose sum is σ = 105539844. Its totient is φ = 70359888.

The previous prime is 87949859. The next prime is 87949903. The reversal of 87949865 is 56894978.

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

It can be written as a sum of positive squares in 2 ways, for example, as 13075456 + 74874409 = 3616^2 + 8653^2 .

It is a cyclic number.

It is not a de Polignac number, because 87949865 - 2⁶ = 87949801 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 87949865.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8794982 + ... + 8794991.

It is an arithmetic number, because the mean of its divisors is an integer number (26384961).

Almost surely, 2^87949865 is an apocalyptic number.

It is an amenable number.

87949865 is a deficient number, since it is larger than the sum of its proper divisors (17589979).

87949865 is a wasteful number, since it uses less digits than its factorization.

87949865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17589978.

The product of its digits is 4354560, while the sum is 56.

The square root of 87949865 is about 9378.1589344604. The cubic root of 87949865 is about 444.7115329450.

The spelling of 87949865 in words is "eighty-seven million, nine hundred forty-nine thousand, eight hundred sixty-five".