5661873521 has 2 divisors, whose sum is σ = 5661873522. Its totient is φ = 5661873520.

The previous prime is 5661873509. The next prime is 5661873577. The reversal of 5661873521 is 1253781665.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5226567025 + 435306496 = 72295^2 + 20864^2 .

It is a cyclic number.

It is not a de Polignac number, because 5661873521 - 2⁶ = 5661873457 is a prime.

It is not a weakly prime, because it can be changed into another prime (5661873421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2830936760 + 2830936761.

It is an arithmetic number, because the mean of its divisors is an integer number (2830936761).

Almost surely, 2^5661873521 is an apocalyptic number.

It is an amenable number.

5661873521 is a deficient number, since it is larger than the sum of its proper divisors (1).

5661873521 is an equidigital number, since it uses as much as digits as its factorization.

5661873521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 302400, while the sum is 44.

The square root of 5661873521 is about 75245.4219271844. The cubic root of 5661873521 is about 1782.3242709786.

The spelling of 5661873521 in words is "five billion, six hundred sixty-one million, eight hundred seventy-three thousand, five hundred twenty-one".