181266940 has 24 divisors (see below), whose sum is σ = 381874752. Its totient is φ = 72275520.

The previous prime is 181266931. The next prime is 181266941. The reversal of 181266940 is 49662181.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 181266940.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181266941) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7956 + ... + 20635.

It is an arithmetic number, because the mean of its divisors is an integer number (15911448).

Almost surely, 2^181266940 is an apocalyptic number.

181266940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

181266940 is an abundant number, since it is smaller than the sum of its proper divisors (200607812).

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

181266940 is a wasteful number, since it uses less digits than its factorization.

181266940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28917 (or 28915 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 181266940 is about 13463.5411389426. The cubic root of 181266940 is about 565.9432282913.

The spelling of 181266940 in words is "one hundred eighty-one million, two hundred sixty-six thousand, nine hundred forty".