28618501 has 4 divisors (see below), whose sum is σ = 29392012. Its totient is φ = 27844992.

The previous prime is 28618489. The next prime is 28618507. The reversal of 28618501 is 10581682.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 18062500 + 10556001 = 4250^2 + 3249^2 .

It is a cyclic number.

It is not a de Polignac number, because 28618501 - 2¹⁷ = 28487429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28618507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 386700 + ... + 386773.

It is an arithmetic number, because the mean of its divisors is an integer number (7348003).

Almost surely, 2^28618501 is an apocalyptic number.

It is an amenable number.

28618501 is a deficient number, since it is larger than the sum of its proper divisors (773511).

28618501 is an equidigital number, since it uses as much as digits as its factorization.

28618501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 773510.

The product of its (nonzero) digits is 3840, while the sum is 31.

The square root of 28618501 is about 5349.6262486271. The cubic root of 28618501 is about 305.8785063133.

The spelling of 28618501 in words is "twenty-eight million, six hundred eighteen thousand, five hundred one".