28312155 has 24 divisors (see below), whose sum is σ = 49271040. Its totient is φ = 15039360.

The previous prime is 28312139. The next prime is 28312159. The reversal of 28312155 is 55121382.

It is a happy number.

It is not a de Polignac number, because 28312155 - 2⁴ = 28312139 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28312159) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11526 + ... + 13764.

It is an arithmetic number, because the mean of its divisors is an integer number (2052960).

Almost surely, 2^28312155 is an apocalyptic number.

28312155 is a deficient number, since it is larger than the sum of its proper divisors (20958885).

28312155 is a wasteful number, since it uses less digits than its factorization.

28312155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2531 (or 2528 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

The square root of 28312155 is about 5320.9167443214. The cubic root of 28312155 is about 304.7831657783.

The spelling of 28312155 in words is "twenty-eight million, three hundred twelve thousand, one hundred fifty-five".