28277779 has 4 divisors (see below), whose sum is σ = 28811376. Its totient is φ = 27744184.

The previous prime is 28277773. The next prime is 28277807. The reversal of 28277779 is 97777282.

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

It is a cyclic number.

It is not a de Polignac number, because 28277779 - 2¹⁹ = 27753491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28277773) 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, 266719 + ... + 266824.

It is an arithmetic number, because the mean of its divisors is an integer number (7202844).

Almost surely, 2^28277779 is an apocalyptic number.

28277779 is a deficient number, since it is larger than the sum of its proper divisors (533597).

28277779 is an equidigital number, since it uses as much as digits as its factorization.

28277779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 533596.

The product of its digits is 691488, while the sum is 49.

The square root of 28277779 is about 5317.6854927684. The cubic root of 28277779 is about 304.6597621332.

The spelling of 28277779 in words is "twenty-eight million, two hundred seventy-seven thousand, seven hundred seventy-nine".