28220502 has 8 divisors (see below), whose sum is σ = 56441016. Its totient is φ = 9406832.

The previous prime is 28220497. The next prime is 28220503. The reversal of 28220502 is 20502282.

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

28220502 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28220503) 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, 2351703 + ... + 2351714.

It is an arithmetic number, because the mean of its divisors is an integer number (7055127).

Almost surely, 2^28220502 is an apocalyptic number.

28220502 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

28220502 is a wasteful number, since it uses less digits than its factorization.

28220502 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4703422.

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 28220502 is about 5312.2972431896. The cubic root of 28220502 is about 304.4539256918.

Adding to 28220502 its reverse (20502282), we get a palindrome (48722784).

The spelling of 28220502 in words is "twenty-eight million, two hundred twenty thousand, five hundred two".