5661551549 has 2 divisors, whose sum is σ = 5661551550. Its totient is φ = 5661551548.

The previous prime is 5661551509. The next prime is 5661551611. The reversal of 5661551549 is 9451551665.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4299424900 + 1362126649 = 65570^2 + 36907^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5661551549 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5661551509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2830775774 + 2830775775.

It is an arithmetic number, because the mean of its divisors is an integer number (2830775775).

Almost surely, 2^5661551549 is an apocalyptic number.

It is an amenable number.

5661551549 is a deficient number, since it is larger than the sum of its proper divisors (1).

5661551549 is an equidigital number, since it uses as much as digits as its factorization.

5661551549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 810000, while the sum is 47.

The square root of 5661551549 is about 75243.2824177680. The cubic root of 5661551549 is about 1782.2904853782.

The spelling of 5661551549 in words is "five billion, six hundred sixty-one million, five hundred fifty-one thousand, five hundred forty-nine".