28780222 has 8 divisors (see below), whose sum is σ = 45047376. Its totient is φ = 13764432.

The previous prime is 28780207. The next prime is 28780223. The reversal of 28780222 is 22208782.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28780223) 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, 312783 + ... + 312874.

It is an arithmetic number, because the mean of its divisors is an integer number (5630922).

Almost surely, 2^28780222 is an apocalyptic number.

28780222 is a deficient number, since it is larger than the sum of its proper divisors (16267154).

28780222 is a wasteful number, since it uses less digits than its factorization.

28780222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 625682.

The product of its (nonzero) digits is 7168, while the sum is 31.

The square root of 28780222 is about 5364.7201231751. The cubic root of 28780222 is about 306.4535899080.

The spelling of 28780222 in words is "twenty-eight million, seven hundred eighty thousand, two hundred twenty-two".