521630842 has 8 divisors (see below), whose sum is σ = 784769076. Its totient is φ = 260041152.

The previous prime is 521630821. The next prime is 521630849. The reversal of 521630842 is 248036125.

It can be written as a sum of positive squares in 2 ways, for example, as 500461641 + 21169201 = 22371^2 + 4601^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (521630849) 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, 386293 + ... + 387640.

Almost surely, 2^521630842 is an apocalyptic number.

521630842 is a deficient number, since it is larger than the sum of its proper divisors (263138234).

521630842 is a wasteful number, since it uses less digits than its factorization.

521630842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 774272.

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 521630842 is about 22839.2390853986. The cubic root of 521630842 is about 804.9849370277.

Adding to 521630842 its reverse (248036125), we get a palindrome (769666967).

The spelling of 521630842 in words is "five hundred twenty-one million, six hundred thirty thousand, eight hundred forty-two".