7921791 has 6 divisors (see below), whose sum is σ = 11442600. Its totient is φ = 5281188.

The previous prime is 7921787. The next prime is 7921817. The reversal of 7921791 is 1971297.

It is not a de Polignac number, because 7921791 - 2² = 7921787 is a prime.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7921391) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 440091 + ... + 440108.

It is an arithmetic number, because the mean of its divisors is an integer number (1907100).

Almost surely, 2^7921791 is an apocalyptic number.

7921791 is a deficient number, since it is larger than the sum of its proper divisors (3520809).

7921791 is a wasteful number, since it uses less digits than its factorization.

7921791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 880205 (or 880202 counting only the distinct ones).

The product of its digits is 7938, while the sum is 36.

The square root of 7921791 is about 2814.5676399760. The cubic root of 7921791 is about 199.3461228867.

The spelling of 7921791 in words is "seven million, nine hundred twenty-one thousand, seven hundred ninety-one".