656530993 has 2 divisors, whose sum is σ = 656530994. Its totient is φ = 656530992.

The previous prime is 656530907. The next prime is 656530999. The reversal of 656530993 is 399035656.

It is a happy number.

656530993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 656230689 + 300304 = 25617^2 + 548^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-656530993 is a prime.

It is not a weakly prime, because it can be changed into another prime (656530999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328265496 + 328265497.

It is an arithmetic number, because the mean of its divisors is an integer number (328265497).

Almost surely, 2^656530993 is an apocalyptic number.

It is an amenable number.

656530993 is a deficient number, since it is larger than the sum of its proper divisors (1).

656530993 is an equidigital number, since it uses as much as digits as its factorization.

656530993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 656100, while the sum is 46.

The square root of 656530993 is about 25622.8607497289. The cubic root of 656530993 is about 869.1306738923.

The spelling of 656530993 in words is "six hundred fifty-six million, five hundred thirty thousand, nine hundred ninety-three".