28640894 has 4 divisors (see below), whose sum is σ = 42961344. Its totient is φ = 14320446.

The previous prime is 28640863. The next prime is 28640917. The reversal of 28640894 is 49804682.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7160222 + ... + 7160225.

It is an arithmetic number, because the mean of its divisors is an integer number (10740336).

Almost surely, 2^28640894 is an apocalyptic number.

28640894 is a deficient number, since it is larger than the sum of its proper divisors (14320450).

28640894 is a wasteful number, since it uses less digits than its factorization.

28640894 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14320449.

The product of its (nonzero) digits is 110592, while the sum is 41.

The square root of 28640894 is about 5351.7187893237. The cubic root of 28640894 is about 305.9582653435.

The spelling of 28640894 in words is "twenty-eight million, six hundred forty thousand, eight hundred ninety-four".