28732261 has 8 divisors (see below), whose sum is σ = 30552984. Its totient is φ = 26926080.

The previous prime is 28732259. The next prime is 28732271. The reversal of 28732261 is 16223782.

It can be written as a sum of positive squares in 4 ways, for example, as 16524225 + 12208036 = 4065^2 + 3494^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28732261 - 2¹ = 28732259 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 (28732271) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 591 + ... + 7603.

It is an arithmetic number, because the mean of its divisors is an integer number (3819123).

Almost surely, 2^28732261 is an apocalyptic number.

It is an amenable number.

28732261 is a deficient number, since it is larger than the sum of its proper divisors (1820723).

28732261 is a wasteful number, since it uses less digits than its factorization.

28732261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7271.

The product of its digits is 8064, while the sum is 31.

The square root of 28732261 is about 5360.2482218644. The cubic root of 28732261 is about 306.2832646916.

The spelling of 28732261 in words is "twenty-eight million, seven hundred thirty-two thousand, two hundred sixty-one".