649138125 has 20 divisors (see below), whose sum is σ = 1081553792. Its totient is φ = 346206000.

The previous prime is 649138123. The next prime is 649138141. The reversal of 649138125 is 521831946.

It is not a de Polignac number, because 649138125 - 2¹ = 649138123 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 (649138121) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 171229 + ... + 174978.

Almost surely, 2^649138125 is an apocalyptic number.

It is an amenable number.

649138125 is a deficient number, since it is larger than the sum of its proper divisors (432415667).

649138125 is an equidigital number, since it uses as much as digits as its factorization.

649138125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 346230 (or 346215 counting only the distinct ones).

The product of its digits is 51840, while the sum is 39.

The square root of 649138125 is about 25478.1892017467. The cubic root of 649138125 is about 865.8560694151.

The spelling of 649138125 in words is "six hundred forty-nine million, one hundred thirty-eight thousand, one hundred twenty-five".