28640667 has 16 divisors (see below), whose sum is σ = 41916672. Its totient is φ = 17250720.

The previous prime is 28640663. The next prime is 28640687. The reversal of 28640667 is 76604682.

It is not a de Polignac number, because 28640667 - 2² = 28640663 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28640663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2913 + ... + 8109.

It is an arithmetic number, because the mean of its divisors is an integer number (2619792).

Almost surely, 2^28640667 is an apocalyptic number.

28640667 is a deficient number, since it is larger than the sum of its proper divisors (13276005).

28640667 is a wasteful number, since it uses less digits than its factorization.

28640667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5378.

The product of its (nonzero) digits is 96768, while the sum is 39.

The square root of 28640667 is about 5351.6975811419. The cubic root of 28640667 is about 305.9574570272.

The spelling of 28640667 in words is "twenty-eight million, six hundred forty thousand, six hundred sixty-seven".