28007990 has 8 divisors (see below), whose sum is σ = 50414400. Its totient is φ = 11203192.

The previous prime is 28007981. The next prime is 28008017. The reversal of 28007990 is 9970082.

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

It is a self number, because there is not a number n which added to its sum of digits gives 28007990.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1400390 + ... + 1400409.

It is an arithmetic number, because the mean of its divisors is an integer number (6301800).

Almost surely, 2^28007990 is an apocalyptic number.

28007990 is a deficient number, since it is larger than the sum of its proper divisors (22406410).

28007990 is a wasteful number, since it uses less digits than its factorization.

28007990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2800806.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 28007990 is about 5292.2575523117. The cubic root of 28007990 is about 303.6877781857.

The spelling of 28007990 in words is "twenty-eight million, seven thousand, nine hundred ninety".