181666272 has 24 divisors (see below), whose sum is σ = 476874216. Its totient is φ = 60555392.

The previous prime is 181666241. The next prime is 181666273. The reversal of 181666272 is 272666181.

It is a tau number, because it is divible by the number of its divisors (24).

It is a self number, because there is not a number n which added to its sum of digits gives 181666272.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181666273) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 946083 + ... + 946274.

It is an arithmetic number, because the mean of its divisors is an integer number (19869759).

Almost surely, 2^181666272 is an apocalyptic number.

181666272 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

181666272 is an abundant number, since it is smaller than the sum of its proper divisors (295207944).

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

181666272 is a wasteful number, since it uses less digits than its factorization.

181666272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1892370 (or 1892362 counting only the distinct ones).

The product of its digits is 48384, while the sum is 39.

The square root of 181666272 is about 13478.3631053626. The cubic root of 181666272 is about 566.3585154270.

Subtracting 181666272 from its reverse (272666181), we obtain a palindrome (90999909).

The spelling of 181666272 in words is "one hundred eighty-one million, six hundred sixty-six thousand, two hundred seventy-two".