28887949 has 4 divisors (see below), whose sum is σ = 28908864. Its totient is φ = 28867036.

The previous prime is 28887941. The next prime is 28887979. The reversal of 28887949 is 94978882.

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: 94978882 = 2 ⋅47489441.

It is a cyclic number.

It is not a de Polignac number, because 28887949 - 2³ = 28887941 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28887949.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28887941) 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, 8227 + ... + 11200.

It is an arithmetic number, because the mean of its divisors is an integer number (7227216).

Almost surely, 2^28887949 is an apocalyptic number.

It is an amenable number.

28887949 is a deficient number, since it is larger than the sum of its proper divisors (20915).

28887949 is a wasteful number, since it uses less digits than its factorization.

28887949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20914.

The product of its digits is 2322432, while the sum is 55.

The square root of 28887949 is about 5374.7510640029. The cubic root of 28887949 is about 306.8354750870.

The spelling of 28887949 in words is "twenty-eight million, eight hundred eighty-seven thousand, nine hundred forty-nine".