7991851 has 12 divisors (see below), whose sum is σ = 9515352. Its totient is φ = 6689088.

The previous prime is 7991839. The next prime is 7991857. The reversal of 7991851 is 1581997.

It is a happy number.

It is not a de Polignac number, because 7991851 - 2⁹ = 7991339 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7991857) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 211 + ... + 4003.

It is an arithmetic number, because the mean of its divisors is an integer number (792946).

Almost surely, 2^7991851 is an apocalyptic number.

7991851 is a deficient number, since it is larger than the sum of its proper divisors (1523501).

7991851 is a wasteful number, since it uses less digits than its factorization.

7991851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3850 (or 3843 counting only the distinct ones).

The product of its digits is 22680, while the sum is 40.

The square root of 7991851 is about 2826.9862044234. The cubic root of 7991851 is about 199.9320685959.

The spelling of 7991851 in words is "seven million, nine hundred ninety-one thousand, eight hundred fifty-one".