521644353612 has 72 divisors (see below), whose sum is σ = 1235624432448. Its totient is φ = 171283932960.

The previous prime is 521644353589. The next prime is 521644353631. The reversal of 521644353612 is 216353446125.

It is a super-2 number, since 2×521644353612² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 86319063 + ... + 86325105.

Almost surely, 2^521644353612 is an apocalyptic number.

It is an amenable number.

521644353612 is an abundant number, since it is smaller than the sum of its proper divisors (713980078836).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

521644353612 is a wasteful number, since it uses less digits than its factorization.

521644353612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7619 (or 7546 counting only the distinct ones).

The product of its digits is 518400, while the sum is 42.

Adding to 521644353612 its reverse (216353446125), we get a palindrome (737997799737).

The spelling of 521644353612 in words is "five hundred twenty-one billion, six hundred forty-four million, three hundred fifty-three thousand, six hundred twelve".