181291968 has 336 divisors, whose sum is σ = 639055872. Its totient is φ = 48384000.

The previous prime is 181291951. The next prime is 181291969. The reversal of 181291968 is 869192181.

It is a super-2 number, since 2×181291968² = 65733555322626048, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

Its product of digits (62208) is a multiple of the sum of its prime factors (144).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181291969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2553373 + ... + 2553443.

It is an arithmetic number, because the mean of its divisors is an integer number (1901952).

Almost surely, 2^181291968 is an apocalyptic number.

181291968 is a gapful number since it is divisible by the number (18) 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 181291968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (319527936).

181291968 is an abundant number, since it is smaller than the sum of its proper divisors (457763904).

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

181291968 is a wasteful number, since it uses less digits than its factorization.

181291968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144 (or 131 counting only the distinct ones).

The product of its digits is 62208, while the sum is 45.

The square root of 181291968 is about 13464.4705800117. The cubic root of 181291968 is about 565.9692741793.

The spelling of 181291968 in words is "one hundred eighty-one million, two hundred ninety-one thousand, nine hundred sixty-eight".