181378772 has 12 divisors (see below), whose sum is σ = 317752596. Its totient is φ = 90592320.

The previous prime is 181378753. The next prime is 181378783. The reversal of 181378772 is 277873181.

It can be written as a sum of positive squares in 2 ways, for example, as 104571076 + 76807696 = 10226^2 + 8764^2 .

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19979 + ... + 27602.

It is an arithmetic number, because the mean of its divisors is an integer number (26479383).

Almost surely, 2^181378772 is an apocalyptic number.

It is an amenable number.

181378772 is a deficient number, since it is larger than the sum of its proper divisors (136373824).

181378772 is a wasteful number, since it uses less digits than its factorization.

181378772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48538 (or 48536 counting only the distinct ones).

The product of its digits is 131712, while the sum is 44.

The square root of 181378772 is about 13467.6936407092. The cubic root of 181378772 is about 566.0595899252.

The spelling of 181378772 in words is "one hundred eighty-one million, three hundred seventy-eight thousand, seven hundred seventy-two".