28078812287 has 4 divisors (see below), whose sum is σ = 28079924400. Its totient is φ = 28077700176.

The previous prime is 28078812253. The next prime is 28078812337. The reversal of 28078812287 is 78221887082.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28078812287 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28078814287) 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, 517283 + ... + 568980.

It is an arithmetic number, because the mean of its divisors is an integer number (7019981100).

Almost surely, 2^28078812287 is an apocalyptic number.

28078812287 is a deficient number, since it is larger than the sum of its proper divisors (1112113).

28078812287 is a wasteful number, since it uses less digits than its factorization.

28078812287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1112112.

The product of its (nonzero) digits is 1605632, while the sum is 53.

The spelling of 28078812287 in words is "twenty-eight billion, seventy-eight million, eight hundred twelve thousand, two hundred eighty-seven".