7971321 has 8 divisors (see below), whose sum is σ = 10690560. Its totient is φ = 5283152.

The previous prime is 7971311. The next prime is 7971323. The reversal of 7971321 is 1231797.

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 7971321 - 2¹⁴ = 7954937 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7971323) 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, 7161 + ... + 8198.

It is an arithmetic number, because the mean of its divisors is an integer number (1336320).

Almost surely, 2^7971321 is an apocalyptic number.

It is an amenable number.

7971321 is a deficient number, since it is larger than the sum of its proper divisors (2719239).

7971321 is a wasteful number, since it uses less digits than its factorization.

7971321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15535.

The product of its digits is 2646, while the sum is 30.

The square root of 7971321 is about 2823.3527941085. The cubic root of 7971321 is about 199.7607221781.

The spelling of 7971321 in words is "seven million, nine hundred seventy-one thousand, three hundred twenty-one".