28951665 has 16 divisors (see below), whose sum is σ = 46433088. Its totient is φ = 15404096.

The previous prime is 28951661. The next prime is 28951667. The reversal of 28951665 is 56615982.

It is a cyclic number.

It is not a de Polignac number, because 28951665 - 2² = 28951661 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28951661) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 4939 + ... + 9071.

It is an arithmetic number, because the mean of its divisors is an integer number (2902068).

Almost surely, 2^28951665 is an apocalyptic number.

It is an amenable number.

28951665 is a deficient number, since it is larger than the sum of its proper divisors (17481423).

28951665 is a wasteful number, since it uses less digits than its factorization.

28951665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4608.

The product of its digits is 129600, while the sum is 42.

The square root of 28951665 is about 5380.6751435113. The cubic root of 28951665 is about 307.0608974958.

It can be divided in two parts, 2895 and 1665, that added together give a triangular number (4560 = T₉₅).

The spelling of 28951665 in words is "twenty-eight million, nine hundred fifty-one thousand, six hundred sixty-five".