8137321 has 4 divisors (see below), whose sum is σ = 8152144. Its totient is φ = 8122500.

The previous prime is 8137303. The next prime is 8137333. The reversal of 8137321 is 1237318.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a 4-Lehmer number, since φ(8137321) divides (8137321-1)⁴.

It is a cyclic number.

It is not a de Polignac number, because 8137321 - 2⁵ = 8137289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8137361) 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, 6555 + ... + 7696.

It is an arithmetic number, because the mean of its divisors is an integer number (2038036).

Almost surely, 2^8137321 is an apocalyptic number.

It is an amenable number.

8137321 is a deficient number, since it is larger than the sum of its proper divisors (14823).

8137321 is a wasteful number, since it uses less digits than its factorization.

8137321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14822.

The product of its digits is 1008, while the sum is 25.

The square root of 8137321 is about 2852.5989903945. The cubic root of 8137321 is about 201.1378558108.

The spelling of 8137321 in words is "eight million, one hundred thirty-seven thousand, three hundred twenty-one".