28731806 has 4 divisors (see below), whose sum is σ = 43097712. Its totient is φ = 14365902.

The previous prime is 28731803. The next prime is 28731809. The reversal of 28731806 is 60813782.

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

It is an interprime number because it is at equal distance from previous prime (28731803) and next prime (28731809).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28731803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7182950 + ... + 7182953.

It is an arithmetic number, because the mean of its divisors is an integer number (10774428).

Almost surely, 2^28731806 is an apocalyptic number.

28731806 is a deficient number, since it is larger than the sum of its proper divisors (14365906).

28731806 is a wasteful number, since it uses less digits than its factorization.

28731806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14365905.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 28731806 is about 5360.2057796320. The cubic root of 28731806 is about 306.2816479303.

The spelling of 28731806 in words is "twenty-eight million, seven hundred thirty-one thousand, eight hundred six".