181722671622 has 72 divisors (see below), whose sum is σ = 418195024416. Its totient is φ = 57020270112.

The previous prime is 181722671621. The next prime is 181722671729. The reversal of 181722671622 is 226176227181.

181722671622 is a `hidden beast` number, since 1 + 8 + 17 + 2 + 2 + 6 + 7 + 1 + 622 = 666.

It is a super-2 number, since 2×181722671622² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181722671621) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 931123 + ... + 1109249.

It is an arithmetic number, because the mean of its divisors is an integer number (5808264228).

Almost surely, 2^181722671622 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 181722671622, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (209097512208).

181722671622 is an abundant number, since it is smaller than the sum of its proper divisors (236472352794).

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

181722671622 is a wasteful number, since it uses less digits than its factorization.

181722671622 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178330 (or 178308 counting only the distinct ones).

The product of its digits is 225792, while the sum is 45.

The spelling of 181722671622 in words is "one hundred eighty-one billion, seven hundred twenty-two million, six hundred seventy-one thousand, six hundred twenty-two".