667656553 has 2 divisors, whose sum is σ = 667656554. Its totient is φ = 667656552.

The previous prime is 667656533. The next prime is 667656557. The reversal of 667656553 is 355656766.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 410791824 + 256864729 = 20268^2 + 16027^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-667656553 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 667656497 and 667656506.

It is not a weakly prime, because it can be changed into another prime (667656557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333828276 + 333828277.

It is an arithmetic number, because the mean of its divisors is an integer number (333828277).

Almost surely, 2^667656553 is an apocalyptic number.

It is an amenable number.

667656553 is a deficient number, since it is larger than the sum of its proper divisors (1).

667656553 is an equidigital number, since it uses as much as digits as its factorization.

667656553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3402000, while the sum is 49.

The square root of 667656553 is about 25839.0509307134. The cubic root of 667656553 is about 874.0126235943.

The spelling of 667656553 in words is "six hundred sixty-seven million, six hundred fifty-six thousand, five hundred fifty-three".