181628728 has 8 divisors (see below), whose sum is σ = 340553880. Its totient is φ = 90814360.

The previous prime is 181628719. The next prime is 181628743. The reversal of 181628728 is 827826181.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11351788 + ... + 11351803.

It is an arithmetic number, because the mean of its divisors is an integer number (42569235).

Almost surely, 2^181628728 is an apocalyptic number.

It is an amenable number.

181628728 is a deficient number, since it is larger than the sum of its proper divisors (158925152).

181628728 is a wasteful number, since it uses less digits than its factorization.

181628728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22703597 (or 22703593 counting only the distinct ones).

The product of its digits is 86016, while the sum is 43.

The square root of 181628728 is about 13476.9702826711. The cubic root of 181628728 is about 566.3194973072.

The spelling of 181628728 in words is "one hundred eighty-one million, six hundred twenty-eight thousand, seven hundred twenty-eight".