1556655553 has 2 divisors, whose sum is σ = 1556655554. Its totient is φ = 1556655552.

The previous prime is 1556655521. The next prime is 1556655559. The reversal of 1556655553 is 3555566551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 831053584 + 725601969 = 28828^2 + 26937^2 .

It is an emirp because it is prime and its reverse (3555566551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1556655553 - 2⁵ = 1556655521 is a prime.

It is not a weakly prime, because it can be changed into another prime (1556655559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 778327776 + 778327777.

It is an arithmetic number, because the mean of its divisors is an integer number (778327777).

Almost surely, 2^1556655553 is an apocalyptic number.

It is an amenable number.

1556655553 is a deficient number, since it is larger than the sum of its proper divisors (1).

1556655553 is an equidigital number, since it uses as much as digits as its factorization.

1556655553 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1687500, while the sum is 46.

The square root of 1556655553 is about 39454.4744357342. The cubic root of 1556655553 is about 1158.9485996884.

The spelling of 1556655553 in words is "one billion, five hundred fifty-six million, six hundred fifty-five thousand, five hundred fifty-three".