12171819660 has 192 divisors, whose sum is σ = 45759458304. Its totient is φ = 2334643200.

The previous prime is 12171819643. The next prime is 12171819697. The reversal of 12171819660 is 6691817121.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 41271 + ... + 161390.

It is an arithmetic number, because the mean of its divisors is an integer number (238330512).

Almost surely, 2^12171819660 is an apocalyptic number.

12171819660 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 12171819660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22879729152).

12171819660 is an abundant number, since it is smaller than the sum of its proper divisors (33587638644).

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

12171819660 is a wasteful number, since it uses less digits than its factorization.

12171819660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202704 (or 202702 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 42.

The spelling of 12171819660 in words is "twelve billion, one hundred seventy-one million, eight hundred nineteen thousand, six hundred sixty".