521666327 has 24 divisors (see below), whose sum is σ = 656252640. Its totient is φ = 405924480.

The previous prime is 521666303. The next prime is 521666339. The reversal of 521666327 is 723666125.

It is not a de Polignac number, because 521666327 - 2¹² = 521662231 is a prime.

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521666347) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 68549 + ... + 75777.

It is an arithmetic number, because the mean of its divisors is an integer number (27343860).

Almost surely, 2^521666327 is an apocalyptic number.

521666327 is a deficient number, since it is larger than the sum of its proper divisors (134586313).

521666327 is a wasteful number, since it uses less digits than its factorization.

521666327 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7323 (or 7310 counting only the distinct ones).

The product of its digits is 90720, while the sum is 38.

The square root of 521666327 is about 22840.0159150558. The cubic root of 521666327 is about 805.0031901935.

The spelling of 521666327 in words is "five hundred twenty-one million, six hundred sixty-six thousand, three hundred twenty-seven".