28387533 has 4 divisors (see below), whose sum is σ = 37850048. Its totient is φ = 18925020.

The previous prime is 28387531. The next prime is 28387561. The reversal of 28387533 is 33578382.

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 not a de Polignac number, because 28387533 - 2¹ = 28387531 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28387491 and 28387500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28387531) 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, 4731253 + ... + 4731258.

It is an arithmetic number, because the mean of its divisors is an integer number (9462512).

Almost surely, 2^28387533 is an apocalyptic number.

It is an amenable number.

28387533 is a deficient number, since it is larger than the sum of its proper divisors (9462515).

28387533 is an equidigital number, since it uses as much as digits as its factorization.

28387533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9462514.

The product of its digits is 120960, while the sum is 39.

The square root of 28387533 is about 5327.9952139618. The cubic root of 28387533 is about 305.0534099783.

It can be divided in two parts, 28387 and 533, that added together give a triangular number (28920 = T₂₄₀).

The spelling of 28387533 in words is "twenty-eight million, three hundred eighty-seven thousand, five hundred thirty-three".