168218144640 has 1728 divisors, whose sum is σ = 774056424960. Its totient is φ = 33359413248.

The previous prime is 168218144639. The next prime is 168218144681. The reversal of 168218144640 is 46441812861.

168218144640 is a `hidden beast` number, since 1 + 6 + 8 + 2 + 181 + 4 + 464 + 0 = 666.

It is a super-2 number, since 2×168218144640² (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 pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 1324552257 + ... + 1324552383.

It is an arithmetic number, because the mean of its divisors is an integer number (447949320).

Almost surely, 2^168218144640 is an apocalyptic number.

168218144640 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 168218144640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (387028212480).

168218144640 is an abundant number, since it is smaller than the sum of its proper divisors (605838280320).

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

168218144640 is a wasteful number, since it uses less digits than its factorization.

168218144640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217 (or 176 counting only the distinct ones).

The product of its (nonzero) digits is 294912, while the sum is 45.

The spelling of 168218144640 in words is "one hundred sixty-eight billion, two hundred eighteen million, one hundred forty-four thousand, six hundred forty".