656661013 has 4 divisors (see below), whose sum is σ = 658609900. Its totient is φ = 654712128.

The previous prime is 656660999. The next prime is 656661059. The reversal of 656661013 is 310166656.

656661013 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 461304484 + 195356529 = 21478^2 + 13977^2 .

It is a cyclic number.

It is not a de Polignac number, because 656661013 - 2¹⁷ = 656529941 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 656661013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656661073) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 973938 + ... + 974611.

It is an arithmetic number, because the mean of its divisors is an integer number (164652475).

Almost surely, 2^656661013 is an apocalyptic number.

It is an amenable number.

656661013 is a deficient number, since it is larger than the sum of its proper divisors (1948887).

656661013 is a wasteful number, since it uses less digits than its factorization.

656661013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1948886.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 656661013 is about 25625.3978115463. The cubic root of 656661013 is about 869.1880445838.

The spelling of 656661013 in words is "six hundred fifty-six million, six hundred sixty-one thousand, thirteen".