28704537 has 10 divisors (see below), whose sum is σ = 42879738. Its totient is φ = 19136304.

The previous prime is 28704527. The next prime is 28704541. The reversal of 28704537 is 73540782.

It can be written as a sum of positive squares in only one way, i.e., 23270976 + 5433561 = 4824^2 + 2331^2 .

It is not a de Polignac number, because 28704537 - 2⁸ = 28704281 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28704527) by changing a digit.

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 9 ways as a sum of consecutive naturals, for example, 177108 + ... + 177269.

Almost surely, 2^28704537 is an apocalyptic number.

28704537 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

28704537 is a deficient number, since it is larger than the sum of its proper divisors (14175201).

28704537 is an equidigital number, since it uses as much as digits as its factorization.

28704537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 354389 (or 354380 counting only the distinct ones).

The product of its (nonzero) digits is 47040, while the sum is 36.

The square root of 28704537 is about 5357.6615234634. The cubic root of 28704537 is about 306.1847212246.

It can be divided in two parts, 28704 and 537, that added together give a square (29241 = 171²).

The spelling of 28704537 in words is "twenty-eight million, seven hundred four thousand, five hundred thirty-seven".