521643618001 has 45 divisors (see below), whose sum is σ = 590925449145. Its totient is φ = 460477072440.

The previous prime is 521643617953. The next prime is 521643618071. The reversal of 521643618001 is 100816346125.

It is a happy number.

The square root of 521643618001 is 722249.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 521643618001 - 2¹¹ = 521643615953 is a prime.

It is a super-2 number, since 2×521643618001² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521643618071) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 4107430000 + ... + 4107430126.

Almost surely, 2^521643618001 is an apocalyptic number.

521643618001 is the 722249-th square number.

521643618001 is the 361125-th centered octagonal number.

It is an amenable number.

521643618001 is a deficient number, since it is larger than the sum of its proper divisors (69281831144).

521643618001 is an frugal number, since it uses more digits than its factorization.

521643618001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392 (or 185 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 37.

The spelling of 521643618001 in words is "five hundred twenty-one billion, six hundred forty-three million, six hundred eighteen thousand, one".