181397656 has 32 divisors (see below), whose sum is σ = 373985280. Its totient is φ = 81799200.

The previous prime is 181397651. The next prime is 181397677. The reversal of 181397656 is 656793181.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181397651) 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, 3061 + ... + 19291.

It is an arithmetic number, because the mean of its divisors is an integer number (11687040).

Almost surely, 2^181397656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 181397656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (186992640).

181397656 is an abundant number, since it is smaller than the sum of its proper divisors (192587624).

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

181397656 is a wasteful number, since it uses less digits than its factorization.

181397656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16375 (or 16371 counting only the distinct ones).

The product of its digits is 272160, while the sum is 46.

The square root of 181397656 is about 13468.3947076109. The cubic root of 181397656 is about 566.0792340806.

The spelling of 181397656 in words is "one hundred eighty-one million, three hundred ninety-seven thousand, six hundred fifty-six".