28212078 has 16 divisors (see below), whose sum is σ = 59743440. Its totient is φ = 8850816.

The previous prime is 28212071. The next prime is 28212097. The reversal of 28212078 is 87021282.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28212071) 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 7 ways as a sum of consecutive naturals, for example, 138193 + ... + 138396.

It is an arithmetic number, because the mean of its divisors is an integer number (3733965).

Almost surely, 2^28212078 is an apocalyptic number.

28212078 is an abundant number, since it is smaller than the sum of its proper divisors (31531362).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28212078 is a wasteful number, since it uses less digits than its factorization.

28212078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276611.

The product of its (nonzero) digits is 3584, while the sum is 30.

The square root of 28212078 is about 5311.5043066913. The cubic root of 28212078 is about 304.4236288636.

The spelling of 28212078 in words is "twenty-eight million, two hundred twelve thousand, seventy-eight".