28731407 has 8 divisors (see below), whose sum is σ = 29339280. Its totient is φ = 28127680.

The previous prime is 28731403. The next prime is 28731433. The reversal of 28731407 is 70413782.

It is a happy number.

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 28731407 - 2² = 28731403 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28731403) 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 7 ways as a sum of consecutive naturals, for example, 15713 + ... + 17445.

It is an arithmetic number, because the mean of its divisors is an integer number (3667410).

Almost surely, 2^28731407 is an apocalyptic number.

28731407 is a deficient number, since it is larger than the sum of its proper divisors (607873).

28731407 is a wasteful number, since it uses less digits than its factorization.

28731407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2073.

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 28731407 is about 5360.1685607824. The cubic root of 28731407 is about 306.2802301410.

The spelling of 28731407 in words is "twenty-eight million, seven hundred thirty-one thousand, four hundred seven".