7918725121 has 4 divisors (see below), whose sum is σ = 7923505732. Its totient is φ = 7913944512.

The previous prime is 7918725107. The next prime is 7918725149. The reversal of 7918725121 is 1215278197.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1215278197 = 7 ⋅173611171.

It can be written as a sum of positive squares in 2 ways, for example, as 2344012225 + 5574712896 = 48415^2 + 74664^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7918725121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7918725161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2387820 + ... + 2391133.

It is an arithmetic number, because the mean of its divisors is an integer number (1980876433).

Almost surely, 2^7918725121 is an apocalyptic number.

It is an amenable number.

7918725121 is a deficient number, since it is larger than the sum of its proper divisors (4780611).

7918725121 is a wasteful number, since it uses less digits than its factorization.

7918725121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4780610.

The product of its digits is 70560, while the sum is 43.

The square root of 7918725121 is about 88987.2188631603. The cubic root of 7918725121 is about 1993.2040269479.

The spelling of 7918725121 in words is "seven billion, nine hundred eighteen million, seven hundred twenty-five thousand, one hundred twenty-one".