28156145 has 8 divisors (see below), whose sum is σ = 33826920. Its totient is φ = 22498560.

The previous prime is 28156133. The next prime is 28156159. The reversal of 28156145 is 54165182.

It can be written as a sum of positive squares in 4 ways, for example, as 456976 + 27699169 = 676^2 + 5263^2 .

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

It is not a de Polignac number, because 28156145 - 2¹⁶ = 28090609 is a prime.

It is a super-2 number, since 2×28156145² = 1585537002522050, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2255 + ... + 7835.

It is an arithmetic number, because the mean of its divisors is an integer number (4228365).

Almost surely, 2^28156145 is an apocalyptic number.

It is an amenable number.

28156145 is a deficient number, since it is larger than the sum of its proper divisors (5670775).

28156145 is a wasteful number, since it uses less digits than its factorization.

28156145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6595.

The product of its digits is 9600, while the sum is 32.

The square root of 28156145 is about 5306.2364251888. The cubic root of 28156145 is about 304.2223132901. Note that the first 3 decimals are identical.

The spelling of 28156145 in words is "twenty-eight million, one hundred fifty-six thousand, one hundred forty-five".