7991331 has 8 divisors (see below), whose sum is σ = 10714704. Its totient is φ = 5297760.

The previous prime is 7991329. The next prime is 7991339. The reversal of 7991331 is 1331997.

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

It is not a de Polignac number, because 7991331 - 2¹ = 7991329 is a prime.

It is a super-2 number, since 2×7991331² = 127722742303122, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 7991292 and 7991301.

It is not an unprimeable number, because it can be changed into a prime (7991339) 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, 6816 + ... + 7901.

It is an arithmetic number, because the mean of its divisors is an integer number (1339338).

Almost surely, 2^7991331 is an apocalyptic number.

7991331 is a deficient number, since it is larger than the sum of its proper divisors (2723373).

7991331 is a wasteful number, since it uses less digits than its factorization.

7991331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14901.

The product of its digits is 5103, while the sum is 33.

The square root of 7991331 is about 2826.8942321919. The cubic root of 7991331 is about 199.9277322233.

The spelling of 7991331 in words is "seven million, nine hundred ninety-one thousand, three hundred thirty-one".