181219942440 has 96 divisors (see below), whose sum is σ = 610778357280. Its totient is φ = 48325315392.

The previous prime is 181219942417. The next prime is 181219942447. The reversal of 181219942440 is 44249912181.

181219942440 is a `hidden beast` number, since 1 + 8 + 1 + 219 + 9 + 424 + 4 + 0 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (181219942447) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9312294 + ... + 9331733.

It is an arithmetic number, because the mean of its divisors is an integer number (6362274555).

Almost surely, 2^181219942440 is an apocalyptic number.

181219942440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

181219942440 is an abundant number, since it is smaller than the sum of its proper divisors (429558414840).

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

181219942440 is a wasteful number, since it uses less digits than its factorization.

181219942440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18644053 (or 18644037 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The spelling of 181219942440 in words is "one hundred eighty-one billion, two hundred nineteen million, nine hundred forty-two thousand, four hundred forty".