521313668 has 6 divisors (see below), whose sum is σ = 912298926. Its totient is φ = 260656832.

The previous prime is 521313649. The next prime is 521313677. The reversal of 521313668 is 866313125.

It can be written as a sum of positive squares in only one way, i.e., 317623684 + 203689984 = 17822^2 + 14272^2 .

It is a super-2 number, since 2×521313668² = 543535880887228448, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65164205 + ... + 65164212.

It is an arithmetic number, because the mean of its divisors is an integer number (152049821).

Almost surely, 2^521313668 is an apocalyptic number.

It is an amenable number.

521313668 is a deficient number, since it is larger than the sum of its proper divisors (390985258).

521313668 is a wasteful number, since it uses less digits than its factorization.

521313668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130328421 (or 130328419 counting only the distinct ones).

The product of its digits is 25920, while the sum is 35.

The square root of 521313668 is about 22832.2944094543. The cubic root of 521313668 is about 804.8217487868.

It can be divided in two parts, 5213 and 13668, that added together give a palindrome (18881).

The spelling of 521313668 in words is "five hundred twenty-one million, three hundred thirteen thousand, six hundred sixty-eight".