99945728 has 18 divisors (see below), whose sum is σ = 199501554. Its totient is φ = 49972736.

The previous prime is 99945721. The next prime is 99945739. The reversal of 99945728 is 82754999.

It can be written as a sum of positive squares in only one way, i.e., 76597504 + 23348224 = 8752^2 + 4832^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 99945728.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99945721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 194951 + ... + 195462.

Almost surely, 2^99945728 is an apocalyptic number.

It is an amenable number.

99945728 is a deficient number, since it is larger than the sum of its proper divisors (99555826).

99945728 is an equidigital number, since it uses as much as digits as its factorization.

99945728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 390429 (or 390415 counting only the distinct ones).

The product of its digits is 1632960, while the sum is 53.

The square root of 99945728 is about 9997.2860317188. The cubic root of 99945728 is about 464.0748987297.

The spelling of 99945728 in words is "ninety-nine million, nine hundred forty-five thousand, seven hundred twenty-eight".