28408749 has 8 divisors (see below), whose sum is σ = 39525312. Its totient is φ = 18115680.

The previous prime is 28408729. The next prime is 28408801. The reversal of 28408749 is 94780482.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28408749 - 2⁷ = 28408621 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 28408749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28408729) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 205792 + ... + 205929.

It is an arithmetic number, because the mean of its divisors is an integer number (4940664).

Almost surely, 2^28408749 is an apocalyptic number.

It is an amenable number.

28408749 is a deficient number, since it is larger than the sum of its proper divisors (11116563).

28408749 is a wasteful number, since it uses less digits than its factorization.

28408749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411747.

The product of its (nonzero) digits is 129024, while the sum is 42.

The square root of 28408749 is about 5329.9858348780. The cubic root of 28408749 is about 305.1293870100.

The spelling of 28408749 in words is "twenty-eight million, four hundred eight thousand, seven hundred forty-nine".