28687990 has 8 divisors (see below), whose sum is σ = 51638400. Its totient is φ = 11475192.

The previous prime is 28687979. The next prime is 28688017. The reversal of 28687990 is 9978682.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1434390 + ... + 1434409.

It is an arithmetic number, because the mean of its divisors is an integer number (6454800).

Almost surely, 2^28687990 is an apocalyptic number.

28687990 is a deficient number, since it is larger than the sum of its proper divisors (22950410).

28687990 is a wasteful number, since it uses less digits than its factorization.

28687990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2868806.

The product of its (nonzero) digits is 435456, while the sum is 49.

The square root of 28687990 is about 5356.1170636946. The cubic root of 28687990 is about 306.1258755629.

The spelling of 28687990 in words is "twenty-eight million, six hundred eighty-seven thousand, nine hundred ninety".