7921907 has 4 divisors (see below), whose sum is σ = 9053616. Its totient is φ = 6790200.

The previous prime is 7921891. The next prime is 7921909. The reversal of 7921907 is 7091297.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 7921907 - 2⁴ = 7921891 is a prime.

It is a super-2 number, since 2×7921907² = 125513221033298, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (7921909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 565844 + ... + 565857.

It is an arithmetic number, because the mean of its divisors is an integer number (2263404).

Almost surely, 2^7921907 is an apocalyptic number.

7921907 is a deficient number, since it is larger than the sum of its proper divisors (1131709).

7921907 is a wasteful number, since it uses less digits than its factorization.

7921907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1131708.

The product of its (nonzero) digits is 7938, while the sum is 35.

The square root of 7921907 is about 2814.5882469733. The cubic root of 7921907 is about 199.3470959005.

The spelling of 7921907 in words is "seven million, nine hundred twenty-one thousand, nine hundred seven".