7123979 has 4 divisors (see below), whose sum is σ = 7163520. Its totient is φ = 7084440.

The previous prime is 7123957. The next prime is 7123981. The reversal of 7123979 is 9793217.

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 7123979 - 2²⁰ = 6075403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7123279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19499 + ... + 19860.

It is an arithmetic number, because the mean of its divisors is an integer number (1790880).

Almost surely, 2^7123979 is an apocalyptic number.

7123979 is a deficient number, since it is larger than the sum of its proper divisors (39541).

7123979 is a wasteful number, since it uses less digits than its factorization.

7123979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39540.

The product of its digits is 23814, while the sum is 38.

The square root of 7123979 is about 2669.0783053331. The cubic root of 7123979 is about 192.4158647338.

The spelling of 7123979 in words is "seven million, one hundred twenty-three thousand, nine hundred seventy-nine".