28253731 has 8 divisors (see below), whose sum is σ = 30900528. Its totient is φ = 25620000.

The previous prime is 28253713. The next prime is 28253747. The reversal of 28253731 is 13735282.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28253731 is a prime.

It is a super-4 number, since 4×28253731⁴ (a number of 31 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28253693 and 28253702.

It is not an unprimeable number, because it can be changed into a prime (28253831) 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, 1581 + ... + 7681.

It is an arithmetic number, because the mean of its divisors is an integer number (3862566).

Almost surely, 2^28253731 is an apocalyptic number.

28253731 is a deficient number, since it is larger than the sum of its proper divisors (2646797).

28253731 is a wasteful number, since it uses less digits than its factorization.

28253731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6533.

The product of its digits is 10080, while the sum is 31.

The square root of 28253731 is about 5315.4238777354. The cubic root of 28253731 is about 304.5733746816.

It can be divided in two parts, 2825 and 3731, that added together give a palindrome (6556).

The spelling of 28253731 in words is "twenty-eight million, two hundred fifty-three thousand, seven hundred thirty-one".