28408977 has 12 divisors (see below), whose sum is σ = 41442804. Its totient is φ = 18751200.

The previous prime is 28408973. The next prime is 28408999. The reversal of 28408977 is 77980482.

It can be written as a sum of positive squares in 2 ways, for example, as 23386896 + 5022081 = 4836^2 + 2241^2 .

It is not a de Polignac number, because 28408977 - 2² = 28408973 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28408973) 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 11 ways as a sum of consecutive naturals, for example, 14718 + ... + 16535.

It is an arithmetic number, because the mean of its divisors is an integer number (3453567).

Almost surely, 2^28408977 is an apocalyptic number.

It is an amenable number.

28408977 is a deficient number, since it is larger than the sum of its proper divisors (13033827).

28408977 is a wasteful number, since it uses less digits than its factorization.

28408977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31360 (or 31357 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The square root of 28408977 is about 5330.0072232596. The cubic root of 28408977 is about 305.1302032998.

The spelling of 28408977 in words is "twenty-eight million, four hundred eight thousand, nine hundred seventy-seven".