550561521997 has 2 divisors, whose sum is σ = 550561521998. Its totient is φ = 550561521996.

The previous prime is 550561521919. The next prime is 550561522003. The reversal of 550561521997 is 799125165055.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 281123704521 + 269437817476 = 530211^2 + 519074^2 .

It is a cyclic number.

It is not a de Polignac number, because 550561521997 - 2⁷ = 550561521869 is a prime.

It is a super-2 number, since 2×550561521997² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (550561521197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 275280760998 + 275280760999.

It is an arithmetic number, because the mean of its divisors is an integer number (275280760999).

Almost surely, 2^550561521997 is an apocalyptic number.

It is an amenable number.

550561521997 is a deficient number, since it is larger than the sum of its proper divisors (1).

550561521997 is an equidigital number, since it uses as much as digits as its factorization.

550561521997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4252500, while the sum is 55.

The spelling of 550561521997 in words is "five hundred fifty billion, five hundred sixty-one million, five hundred twenty-one thousand, nine hundred ninety-seven".