28125155 has 4 divisors (see below), whose sum is σ = 33750192. Its totient is φ = 22500120.

The previous prime is 28125127. The next prime is 28125169. The reversal of 28125155 is 55152182.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 28125155 - 2²⁰ = 27076579 is a prime.

It is a Duffinian 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, 2812511 + ... + 2812520.

It is an arithmetic number, because the mean of its divisors is an integer number (8437548).

Almost surely, 2^28125155 is an apocalyptic number.

28125155 is a deficient number, since it is larger than the sum of its proper divisors (5625037).

28125155 is an equidigital number, since it uses as much as digits as its factorization.

28125155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5625036.

The product of its digits is 4000, while the sum is 29.

The square root of 28125155 is about 5303.3154724191. The cubic root of 28125155 is about 304.1106584392.

The spelling of 28125155 in words is "twenty-eight million, one hundred twenty-five thousand, one hundred fifty-five".