28783928 has 32 divisors (see below), whose sum is σ = 56635200. Its totient is φ = 13698432.

The previous prime is 28783919. The next prime is 28783933. The reversal of 28783928 is 82938782.

It is a super-2 number, since 2×28783928² = 1657029022218368, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12878 + ... + 14946.

It is an arithmetic number, because the mean of its divisors is an integer number (1769850).

Almost surely, 2^28783928 is an apocalyptic number.

It is an amenable number.

28783928 is a deficient number, since it is larger than the sum of its proper divisors (27851272).

28783928 is a wasteful number, since it uses less digits than its factorization.

28783928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2159 (or 2155 counting only the distinct ones).

The product of its digits is 387072, while the sum is 47.

The square root of 28783928 is about 5365.0655168413. The cubic root of 28783928 is about 306.4667432494.

The spelling of 28783928 in words is "twenty-eight million, seven hundred eighty-three thousand, nine hundred twenty-eight".