28011890 has 32 divisors (see below), whose sum is σ = 53352000. Its totient is φ = 10559808.

The previous prime is 28011857. The next prime is 28011901. The reversal of 28011890 is 9811082.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71816 + ... + 72204.

It is an arithmetic number, because the mean of its divisors is an integer number (1667250).

Almost surely, 2^28011890 is an apocalyptic number.

28011890 is a deficient number, since it is larger than the sum of its proper divisors (25340110).

28011890 is a wasteful number, since it uses less digits than its factorization.

28011890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 794.

The product of its (nonzero) digits is 1152, while the sum is 29.

The square root of 28011890 is about 5292.6260022790. The cubic root of 28011890 is about 303.7018732989.

The spelling of 28011890 in words is "twenty-eight million, eleven thousand, eight hundred ninety".