656007021643 has 2 divisors, whose sum is σ = 656007021644. Its totient is φ = 656007021642.

The previous prime is 656007021623. The next prime is 656007021647. The reversal of 656007021643 is 346120700656.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-656007021643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 656007021596 and 656007021605.

It is not a weakly prime, because it can be changed into another prime (656007021647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328003510821 + 328003510822.

It is an arithmetic number, because the mean of its divisors is an integer number (328003510822).

Almost surely, 2^656007021643 is an apocalyptic number.

656007021643 is a deficient number, since it is larger than the sum of its proper divisors (1).

656007021643 is an equidigital number, since it uses as much as digits as its factorization.

656007021643 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 181440, while the sum is 40.

The spelling of 656007021643 in words is "six hundred fifty-six billion, seven million, twenty-one thousand, six hundred forty-three".