28777987 has 16 divisors (see below), whose sum is σ = 33625600. Its totient is φ = 24121152.

The previous prime is 28777981. The next prime is 28777997. The reversal of 28777987 is 78977782.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 28777987 - 2³ = 28777979 is a prime.

It is a super-3 number, since 3×28777987³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28777981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 101548 + ... + 101830.

It is an arithmetic number, because the mean of its divisors is an integer number (2101600).

Almost surely, 2^28777987 is an apocalyptic number.

28777987 is a deficient number, since it is larger than the sum of its proper divisors (4847613).

28777987 is a wasteful number, since it uses less digits than its factorization.

28777987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562.

The product of its digits is 2765952, while the sum is 55.

The square root of 28777987 is about 5364.5118137627. The cubic root of 28777987 is about 306.4456568964.

The spelling of 28777987 in words is "twenty-eight million, seven hundred seventy-seven thousand, nine hundred eighty-seven".