8205139 has 4 divisors (see below), whose sum is σ = 8286480. Its totient is φ = 8123800.

The previous prime is 8205137. The next prime is 8205143. The reversal of 8205139 is 9315028.

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 8205139 - 2¹ = 8205137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8205137) 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, 40519 + ... + 40720.

It is an arithmetic number, because the mean of its divisors is an integer number (2071620).

Almost surely, 2^8205139 is an apocalyptic number.

8205139 is a deficient number, since it is larger than the sum of its proper divisors (81341).

8205139 is a wasteful number, since it uses less digits than its factorization.

8205139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81340.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 8205139 is about 2864.4613804344. The cubic root of 8205139 is about 201.6950845214.

The spelling of 8205139 in words is "eight million, two hundred five thousand, one hundred thirty-nine".