28021768 has 32 divisors (see below), whose sum is σ = 54812160. Its totient is φ = 13415040.

The previous prime is 28021757. The next prime is 28021769. The reversal of 28021768 is 86712082.

It is not an unprimeable number, because it can be changed into a prime (28021769) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24996 + ... + 26092.

It is an arithmetic number, because the mean of its divisors is an integer number (1712880).

Almost surely, 2^28021768 is an apocalyptic number.

It is an amenable number.

28021768 is a deficient number, since it is larger than the sum of its proper divisors (26790392).

28021768 is a wasteful number, since it uses less digits than its factorization.

28021768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1237 (or 1233 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 34.

The square root of 28021768 is about 5293.5591051768. The cubic root of 28021768 is about 303.7375678384.

The spelling of 28021768 in words is "twenty-eight million, twenty-one thousand, seven hundred sixty-eight".