660648513 has 32 divisors (see below), whose sum is σ = 1025740800. Its totient is φ = 370440576.

The previous prime is 660648491. The next prime is 660648523. The reversal of 660648513 is 315846066.

It is not a de Polignac number, because 660648513 - 2⁸ = 660648257 is a prime.

It is a super-2 number, since 2×660648513² = 872912915458222338, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (660648523) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 258520 + ... + 261062.

It is an arithmetic number, because the mean of its divisors is an integer number (32054400).

Almost surely, 2^660648513 is an apocalyptic number.

It is an amenable number.

660648513 is a deficient number, since it is larger than the sum of its proper divisors (365092287).

660648513 is a wasteful number, since it uses less digits than its factorization.

660648513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2781.

The product of its (nonzero) digits is 103680, while the sum is 39.

The square root of 660648513 is about 25703.0837254988. The cubic root of 660648513 is about 870.9438442162.

The spelling of 660648513 in words is "six hundred sixty million, six hundred forty-eight thousand, five hundred thirteen".