28251553 has 4 divisors (see below), whose sum is σ = 30819888. Its totient is φ = 25683220.

The previous prime is 28251547. The next prime is 28251563. The reversal of 28251553 is 35515282.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28251553 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 not an unprimeable number, because it can be changed into a prime (28251563) 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, 1284151 + ... + 1284172.

It is an arithmetic number, because the mean of its divisors is an integer number (7704972).

Almost surely, 2^28251553 is an apocalyptic number.

It is an amenable number.

28251553 is a deficient number, since it is larger than the sum of its proper divisors (2568335).

28251553 is a wasteful number, since it uses less digits than its factorization.

28251553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2568334.

The product of its digits is 12000, while the sum is 31.

The square root of 28251553 is about 5315.2189983104. The cubic root of 28251553 is about 304.5655482479.

The spelling of 28251553 in words is "twenty-eight million, two hundred fifty-one thousand, five hundred fifty-three".