28015998 has 8 divisors (see below), whose sum is σ = 56032008. Its totient is φ = 9338664.

The previous prime is 28015987. The next prime is 28016003. The reversal of 28015998 is 89951082.

It is a happy number.

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

28015998 is an admirable number.

It is a super-2 number, since 2×28015998² = 1569792287872008, which contains 22 as substring.

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, 2334661 + ... + 2334672.

It is an arithmetic number, because the mean of its divisors is an integer number (7004001).

Almost surely, 2^28015998 is an apocalyptic number.

28015998 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28015998 is a wasteful number, since it uses less digits than its factorization.

28015998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4669338.

The product of its (nonzero) digits is 51840, while the sum is 42.

The square root of 28015998 is about 5293.0140751749. The cubic root of 28015998 is about 303.7167187367.

The spelling of 28015998 in words is "twenty-eight million, fifteen thousand, nine hundred ninety-eight".