28921749 has 8 divisors (see below), whose sum is σ = 38587680. Its totient is φ = 19268496.

The previous prime is 28921727. The next prime is 28921771. The reversal of 28921749 is 94712982.

It is an interprime number because it is at equal distance from previous prime (28921727) and next prime (28921771).

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

It is not a de Polignac number, because 28921749 - 2⁹ = 28921237 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28921749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28921349) 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, 5719 + ... + 9515.

It is an arithmetic number, because the mean of its divisors is an integer number (4823460).

Almost surely, 2^28921749 is an apocalyptic number.

It is an amenable number.

28921749 is a deficient number, since it is larger than the sum of its proper divisors (9665931).

28921749 is a wasteful number, since it uses less digits than its factorization.

28921749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6339.

The product of its digits is 72576, while the sum is 42.

The square root of 28921749 is about 5377.8944764657. The cubic root of 28921749 is about 306.9550981733.

The spelling of 28921749 in words is "twenty-eight million, nine hundred twenty-one thousand, seven hundred forty-nine".