521061866 has 32 divisors (see below), whose sum is σ = 912997008. Its totient is φ = 220815360.

The previous prime is 521061847. The next prime is 521061869. The reversal of 521061866 is 668160125.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 222636241 + 298425625 = 14921^2 + 17275^2 .

It is not an unprimeable number, because it can be changed into a prime (521061869) 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 in 15 ways as a sum of consecutive naturals, for example, 3746 + ... + 32498.

Almost surely, 2^521061866 is an apocalyptic number.

521061866 is a deficient number, since it is larger than the sum of its proper divisors (391935142).

521061866 is a wasteful number, since it uses less digits than its factorization.

521061866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28826.

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 521061866 is about 22826.7795801335. The cubic root of 521061866 is about 804.6921477579.

It can be divided in two parts, 5210 and 61866, that added together give a palindrome (67076).

The spelling of 521061866 in words is "five hundred twenty-one million, sixty-one thousand, eight hundred sixty-six".