28391155 has 12 divisors (see below), whose sum is σ = 36892800. Its totient is φ = 20965152.

The previous prime is 28391141. The next prime is 28391179. The reversal of 28391155 is 55119382.

It is not a de Polignac number, because 28391155 - 2⁵ = 28391123 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28391155.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15955 + ... + 17644.

It is an arithmetic number, because the mean of its divisors is an integer number (3074400).

Almost surely, 2^28391155 is an apocalyptic number.

28391155 is a deficient number, since it is larger than the sum of its proper divisors (8501645).

28391155 is a wasteful number, since it uses less digits than its factorization.

28391155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33630 (or 33617 counting only the distinct ones).

The product of its digits is 10800, while the sum is 34.

The square root of 28391155 is about 5328.3351058281. The cubic root of 28391155 is about 305.0663834722.

The spelling of 28391155 in words is "twenty-eight million, three hundred ninety-one thousand, one hundred fifty-five".