6646977125 has 8 divisors (see below), whose sum is σ = 8295427608. Its totient is φ = 5317581600.

The previous prime is 6646977121. The next prime is 6646977133. The reversal of 6646977125 is 5217796466.

It can be written as a sum of positive squares in 4 ways, for example, as 218625796 + 6428351329 = 14786^2 + 80177^2 .

It is not a de Polignac number, because 6646977125 - 2² = 6646977121 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6646977121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26587784 + ... + 26588033.

It is an arithmetic number, because the mean of its divisors is an integer number (1036928451).

Almost surely, 2^6646977125 is an apocalyptic number.

It is an amenable number.

6646977125 is a deficient number, since it is larger than the sum of its proper divisors (1648450483).

6646977125 is an equidigital number, since it uses as much as digits as its factorization.

6646977125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53175832 (or 53175822 counting only the distinct ones).

The product of its digits is 3810240, while the sum is 53.

The square root of 6646977125 is about 81528.9956089243. The cubic root of 6646977125 is about 1880.2173738581.

The spelling of 6646977125 in words is "six billion, six hundred forty-six million, nine hundred seventy-seven thousand, one hundred twenty-five".