28212783 has 4 divisors (see below), whose sum is σ = 37617048. Its totient is φ = 18808520.

The previous prime is 28212781. The next prime is 28212791. The reversal of 28212783 is 38721282.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28212783 - 2¹ = 28212781 is a prime.

It is a super-2 number, since 2×28212783² = 1591922249210178, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28212781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4702128 + ... + 4702133.

It is an arithmetic number, because the mean of its divisors is an integer number (9404262).

Almost surely, 2^28212783 is an apocalyptic number.

28212783 is a deficient number, since it is larger than the sum of its proper divisors (9404265).

28212783 is an equidigital number, since it uses as much as digits as its factorization.

28212783 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9404264.

The product of its digits is 10752, while the sum is 33.

The square root of 28212783 is about 5311.5706716564. The cubic root of 28212783 is about 304.4261646199.

The spelling of 28212783 in words is "twenty-eight million, two hundred twelve thousand, seven hundred eighty-three".