171993796520 has 256 divisors, whose sum is σ = 511600320000. Its totient is φ = 51567280128.

The previous prime is 171993796517. The next prime is 171993796523. The reversal of 171993796520 is 25697399171.

It is an interprime number because it is at equal distance from previous prime (171993796517) and next prime (171993796523).

It is a super-2 number, since 2×171993796520² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 171993796520.

It is not an unprimeable number, because it can be changed into a prime (171993796523) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3363464 + ... + 3414216.

It is an arithmetic number, because the mean of its divisors is an integer number (1998438750).

Almost surely, 2^171993796520 is an apocalyptic number.

171993796520 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 171993796520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (255800160000).

171993796520 is an abundant number, since it is smaller than the sum of its proper divisors (339606523480).

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

171993796520 is a wasteful number, since it uses less digits than its factorization.

171993796520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50817 (or 50799 counting only the distinct ones).

The product of its (nonzero) digits is 6429780, while the sum is 59.

The spelling of 171993796520 in words is "one hundred seventy-one billion, nine hundred ninety-three million, seven hundred ninety-six thousand, five hundred twenty".