521774842 has 4 divisors (see below), whose sum is σ = 782662266. Its totient is φ = 260887420.

The previous prime is 521774837. The next prime is 521774861. The reversal of 521774842 is 248477125.

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

It can be written as a sum of positive squares in only one way, i.e., 482724841 + 39050001 = 21971^2 + 6249^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 521774795 and 521774804.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130443709 + ... + 130443712.

Almost surely, 2^521774842 is an apocalyptic number.

521774842 is a deficient number, since it is larger than the sum of its proper divisors (260887424).

521774842 is a wasteful number, since it uses less digits than its factorization.

521774842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260887423.

The product of its digits is 125440, while the sum is 40.

The square root of 521774842 is about 22842.3913371608. The cubic root of 521774842 is about 805.0590042010.

The spelling of 521774842 in words is "five hundred twenty-one million, seven hundred seventy-four thousand, eight hundred forty-two".