521481673 has 4 divisors (see below), whose sum is σ = 524981700. Its totient is φ = 517981648.

The previous prime is 521481661. The next prime is 521481679. The reversal of 521481673 is 376184125.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 99261369 + 422220304 = 9963^2 + 20548^2 .

It is a cyclic number.

It is not a de Polignac number, because 521481673 - 2⁵ = 521481641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521481679) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1749790 + ... + 1750087.

It is an arithmetic number, because the mean of its divisors is an integer number (131245425).

Almost surely, 2^521481673 is an apocalyptic number.

It is an amenable number.

521481673 is a deficient number, since it is larger than the sum of its proper divisors (3500027).

521481673 is a wasteful number, since it uses less digits than its factorization.

521481673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3500026.

The product of its digits is 40320, while the sum is 37.

The square root of 521481673 is about 22835.9732220897. The cubic root of 521481673 is about 804.9081967761.

The spelling of 521481673 in words is "five hundred twenty-one million, four hundred eighty-one thousand, six hundred seventy-three".