28417261 has 4 divisors (see below), whose sum is σ = 28528092. Its totient is φ = 28306432.

The previous prime is 28417247. The next prime is 28417267. The reversal of 28417261 is 16271482.

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 25694761 + 2722500 = 5069^2 + 1650^2 .

It is a cyclic number.

It is not a de Polignac number, because 28417261 - 2⁹ = 28416749 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28417267) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55030 + ... + 55543.

It is an arithmetic number, because the mean of its divisors is an integer number (7132023).

Almost surely, 2^28417261 is an apocalyptic number.

It is an amenable number.

28417261 is a deficient number, since it is larger than the sum of its proper divisors (110831).

28417261 is a wasteful number, since it uses less digits than its factorization.

28417261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110830.

The product of its digits is 5376, while the sum is 31.

The square root of 28417261 is about 5330.7842762580. The cubic root of 28417261 is about 305.1598588667.

The spelling of 28417261 in words is "twenty-eight million, four hundred seventeen thousand, two hundred sixty-one".