28691968 has 20 divisors (see below), whose sum is σ = 57328920. Its totient is φ = 14345728.

The previous prime is 28691953. The next prime is 28691969. The reversal of 28691968 is 86919682.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28691969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27508 + ... + 28531.

It is an arithmetic number, because the mean of its divisors is an integer number (2866446).

Almost surely, 2^28691968 is an apocalyptic number.

It is an amenable number.

28691968 is a deficient number, since it is larger than the sum of its proper divisors (28636952).

28691968 is an frugal number, since it uses more digits than its factorization.

28691968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56057 (or 56041 counting only the distinct ones).

The product of its digits is 373248, while the sum is 49.

The square root of 28691968 is about 5356.4884019290. The cubic root of 28691968 is about 306.1400244855.

The spelling of 28691968 in words is "twenty-eight million, six hundred ninety-one thousand, nine hundred sixty-eight".