521678361 has 16 divisors (see below), whose sum is σ = 721316160. Its totient is φ = 334971840.

The previous prime is 521678357. The next prime is 521678401. The reversal of 521678361 is 163876125.

It is not a de Polignac number, because 521678361 - 2² = 521678357 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (521678321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29506 + ... + 43748.

It is an arithmetic number, because the mean of its divisors is an integer number (45082260).

Almost surely, 2^521678361 is an apocalyptic number.

521678361 is the 12209-th nonagonal number.

It is an amenable number.

521678361 is a deficient number, since it is larger than the sum of its proper divisors (199637799).

521678361 is a wasteful number, since it uses less digits than its factorization.

521678361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14696.

The product of its digits is 60480, while the sum is 39.

The square root of 521678361 is about 22840.2793546839. The cubic root of 521678361 is about 805.0093801872.

The spelling of 521678361 in words is "five hundred twenty-one million, six hundred seventy-eight thousand, three hundred sixty-one".