7991811 has 8 divisors (see below), whose sum is σ = 11839760. Its totient is φ = 5327856.

The previous prime is 7991803. The next prime is 7991839. The reversal of 7991811 is 1181997.

It is not a de Polignac number, because 7991811 - 2³ = 7991803 is a prime.

It is a Duffinian number.

7991811 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (7991891) 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, 147970 + ... + 148023.

It is an arithmetic number, because the mean of its divisors is an integer number (1479970).

Almost surely, 2^7991811 is an apocalyptic number.

7991811 is a deficient number, since it is larger than the sum of its proper divisors (3847949).

7991811 is a wasteful number, since it uses less digits than its factorization.

7991811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296002 (or 295996 counting only the distinct ones).

The product of its digits is 4536, while the sum is 36.

The square root of 7991811 is about 2826.9791297426. The cubic root of 7991811 is about 199.9317350355.

The spelling of 7991811 in words is "seven million, nine hundred ninety-one thousand, eight hundred eleven".