162617821081 has 27 divisors (see below), whose sum is σ = 172804247581. Its totient is φ = 153019047104.

The previous prime is 162617821073. The next prime is 162617821087. The reversal of 162617821081 is 180128716261.

The square root of 162617821081 is 403259.

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

It can be written as a sum of positive squares in 4 ways, for example, as 15226326025 + 147391495056 = 123395^2 + 383916^2 .

It is not a de Polignac number, because 162617821081 - 2³ = 162617821073 is a prime.

It is a super-2 number, since 2×162617821081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (162617821087) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 825471075 + ... + 825471271.

Almost surely, 2^162617821081 is an apocalyptic number.

162617821081 is the 403259-th square number.

162617821081 is the 201630-th centered octagonal number.

It is an amenable number.

162617821081 is a deficient number, since it is larger than the sum of its proper divisors (10186426500).

162617821081 is an frugal number, since it uses more digits than its factorization.

162617821081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 618 (or 309 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 43.

The spelling of 162617821081 in words is "one hundred sixty-two billion, six hundred seventeen million, eight hundred twenty-one thousand, eighty-one".