171611396820 has 384 divisors, whose sum is σ = 584422003200. Its totient is φ = 42175157760.

The previous prime is 171611396813. The next prime is 171611396843. The reversal of 171611396820 is 28693116171.

171611396820 is a `hidden beast` number, since 1 + 7 + 1 + 611 + 3 + 9 + 6 + 8 + 20 = 666.

It is a super-2 number, since 2×171611396820² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 30746430 + ... + 30752010.

It is an arithmetic number, because the mean of its divisors is an integer number (1521932300).

Almost surely, 2^171611396820 is an apocalyptic number.

171611396820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 171611396820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (292211001600).

171611396820 is an abundant number, since it is smaller than the sum of its proper divisors (412810606380).

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

171611396820 is a wasteful number, since it uses less digits than its factorization.

171611396820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5667 (or 5647 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The spelling of 171611396820 in words is "one hundred seventy-one billion, six hundred eleven million, three hundred ninety-six thousand, eight hundred twenty".