7858125665 has 12 divisors (see below), whose sum is σ = 10210914684. Its totient is φ = 5802922944.

The previous prime is 7858125643. The next prime is 7858125677. The reversal of 7858125665 is 5665218587.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 3548465761 + 4309659904 = 59569^2 + 65648^2 .

It is not a de Polignac number, because 7858125665 - 2⁸ = 7858125409 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 4648934 + ... + 4650623.

It is an arithmetic number, because the mean of its divisors is an integer number (850909557).

Almost surely, 2^7858125665 is an apocalyptic number.

It is an amenable number.

7858125665 is a deficient number, since it is larger than the sum of its proper divisors (2352789019).

7858125665 is a wasteful number, since it uses less digits than its factorization.

7858125665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9299588 (or 9299575 counting only the distinct ones).

The product of its digits is 4032000, while the sum is 53.

The square root of 7858125665 is about 88646.0696534257. The cubic root of 7858125665 is about 1988.1065518942.

The spelling of 7858125665 in words is "seven billion, eight hundred fifty-eight million, one hundred twenty-five thousand, six hundred sixty-five".