28780078 has 8 divisors (see below), whose sum is σ = 43200072. Its totient is φ = 14380056.

The previous prime is 28780067. The next prime is 28780109. The reversal of 28780078 is 87008782.

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

It is a super-4 number, since 4×28780078⁴ (a number of 31 digits) contains 4444 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28780078.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 625 + ... + 7612.

It is an arithmetic number, because the mean of its divisors is an integer number (5400009).

Almost surely, 2^28780078 is an apocalyptic number.

28780078 is a deficient number, since it is larger than the sum of its proper divisors (14419994).

28780078 is a wasteful number, since it uses less digits than its factorization.

28780078 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9986.

The product of its (nonzero) digits is 50176, while the sum is 40.

The square root of 28780078 is about 5364.7067021413. The cubic root of 28780078 is about 306.4530788001.

The spelling of 28780078 in words is "twenty-eight million, seven hundred eighty thousand, seventy-eight".