28201649 has 4 divisors (see below), whose sum is σ = 32230464. Its totient is φ = 24172836.

The previous prime is 28201639. The next prime is 28201673. The reversal of 28201649 is 94610282.

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.

It is a cyclic number.

It is not a de Polignac number, because 28201649 - 2²⁴ = 11424433 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28201609) 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, 2014397 + ... + 2014410.

It is an arithmetic number, because the mean of its divisors is an integer number (8057616).

Almost surely, 2^28201649 is an apocalyptic number.

It is an amenable number.

28201649 is a deficient number, since it is larger than the sum of its proper divisors (4028815).

28201649 is an equidigital number, since it uses as much as digits as its factorization.

28201649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4028814.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 28201649 is about 5310.5224790034. The cubic root of 28201649 is about 304.3861127175.

The spelling of 28201649 in words is "twenty-eight million, two hundred one thousand, six hundred forty-nine".