28771647 has 4 divisors (see below), whose sum is σ = 38362200. Its totient is φ = 19181096.

The previous prime is 28771591. The next prime is 28771651. The reversal of 28771647 is 74617782.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28771647 - 2⁶ = 28771583 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28771599 and 28771608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28771657) 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, 4795272 + ... + 4795277.

It is an arithmetic number, because the mean of its divisors is an integer number (9590550).

Almost surely, 2^28771647 is an apocalyptic number.

28771647 is a deficient number, since it is larger than the sum of its proper divisors (9590553).

28771647 is an equidigital number, since it uses as much as digits as its factorization.

28771647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9590552.

The product of its digits is 131712, while the sum is 42.

The square root of 28771647 is about 5363.9208607137. The cubic root of 28771647 is about 306.4231511740.

The spelling of 28771647 in words is "twenty-eight million, seven hundred seventy-one thousand, six hundred forty-seven".