352718861817721 has 81 divisors (see below), whose sum is σ = 432251758311471. Its totient is φ = 286956969403104.

The previous prime is 352718861817703. The next prime is 352718861817727. The reversal of 352718861817721 is 127718168817253.

The square root of 352718861817721 is 18780811.

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

It can be written as a sum of positive squares in only one way, i.e., 103387308882025 + 249331552935696 = 10167955^2 + 15790236^2 .

It is not a de Polignac number, because 352718861817721 - 2¹¹ = 352718861815673 is a prime.

It is a super-2 number, since 2×352718861817721² (a number of 30 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (352718861817727) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 474722559276 + ... + 474722560018.

Almost surely, 2^{352718861817721} is an apocalyptic number.

352718861817721 is the 18780811-st square number.

352718861817721 is the 9390406-th centered octagonal number.

It is an amenable number.

352718861817721 is a deficient number, since it is larger than the sum of its proper divisors (79532896493750).

352718861817721 is an frugal number, since it uses more digits than its factorization.

352718861817721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1860 (or 930 counting only the distinct ones).

The product of its digits is 63221760, while the sum is 67.

The spelling of 352718861817721 in words is "three hundred fifty-two trillion, seven hundred eighteen billion, eight hundred sixty-one million, eight hundred seventeen thousand, seven hundred twenty-one".