28940647 has 8 divisors (see below), whose sum is σ = 31975776. Its totient is φ = 26053632.

The previous prime is 28940627. The next prime is 28940663. The reversal of 28940647 is 74604982.

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

It is a cyclic number.

It is not a de Polignac number, because 28940647 - 2¹¹ = 28938599 is a prime.

It is a super-2 number, since 2×28940647² = 1675122097557218, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28940627) 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, 36618 + ... + 37399.

It is an arithmetic number, because the mean of its divisors is an integer number (3996972).

Almost surely, 2^28940647 is an apocalyptic number.

28940647 is a deficient number, since it is larger than the sum of its proper divisors (3035129).

28940647 is a wasteful number, since it uses less digits than its factorization.

28940647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74057.

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 28940647 is about 5379.6511968714. The cubic root of 28940647 is about 307.0219403093.

The spelling of 28940647 in words is "twenty-eight million, nine hundred forty thousand, six hundred forty-seven".