20556555433 has 2 divisors, whose sum is σ = 20556555434. Its totient is φ = 20556555432.

The previous prime is 20556555427. The next prime is 20556555511. The reversal of 20556555433 is 33455565502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17781689104 + 2774866329 = 133348^2 + 52677^2 .

It is a cyclic number.

It is not a de Polignac number, because 20556555433 - 2⁵ = 20556555401 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20556555433.

It is not a weakly prime, because it can be changed into another prime (20556555413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10278277716 + 10278277717.

It is an arithmetic number, because the mean of its divisors is an integer number (10278277717).

Almost surely, 2^20556555433 is an apocalyptic number.

It is an amenable number.

20556555433 is a deficient number, since it is larger than the sum of its proper divisors (1).

20556555433 is an equidigital number, since it uses as much as digits as its factorization.

20556555433 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1350000, while the sum is 43.

The spelling of 20556555433 in words is "twenty billion, five hundred fifty-six million, five hundred fifty-five thousand, four hundred thirty-three".