8121985 has 8 divisors (see below), whose sum is σ = 9930600. Its totient is φ = 6374784.

The previous prime is 8121983. The next prime is 8121991. The reversal of 8121985 is 5891218.

It can be written as a sum of positive squares in 4 ways, for example, as 101761 + 8020224 = 319^2 + 2832^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 8121985 - 2¹ = 8121983 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 8121985.

It is not an unprimeable number, because it can be changed into a prime (8121983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15060 + ... + 15589.

It is an arithmetic number, because the mean of its divisors is an integer number (1241325).

Almost surely, 2^8121985 is an apocalyptic number.

It is an amenable number.

8121985 is a deficient number, since it is larger than the sum of its proper divisors (1808615).

8121985 is a wasteful number, since it uses less digits than its factorization.

8121985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30707.

The product of its digits is 5760, while the sum is 34.

The square root of 8121985 is about 2849.9096476906. The cubic root of 8121985 is about 201.0114182106.

The spelling of 8121985 in words is "eight million, one hundred twenty-one thousand, nine hundred eighty-five".