28449901 has 4 divisors (see below), whose sum is σ = 28462752.
Its totient is φ = 28437052.
The previous prime is 28449893. The next prime is 28449907. The reversal of 28449901 is 10994482.
It is a happy number.
It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 10994482 = 2 ⋅5497241.
It is a cyclic number.
It is not a de Polignac number, because 28449901 - 23 = 28449893 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 (28449907) 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 3 ways as a sum of consecutive naturals, for example, 2161 + ... + 7846.
It is an arithmetic number, because the mean of its divisors is an integer number (7115688).
It is a 2214-hyperperfect number.
Almost surely, 228449901 is an apocalyptic number.
It is an amenable number.
28449901 is a deficient number, since it is larger than the sum of its proper divisors (12851).
28449901 is a wasteful number, since it uses less digits than its factorization.
28449901 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 12850.
The product of its (nonzero) digits is 20736, while the sum is 37.
The square root of 28449901 is about 5333.8448608860.
The cubic root of 28449901 is about 305.2766494647.
The spelling of 28449901 in words is "twenty-eight million, four hundred forty-nine thousand, nine hundred one".