28078920 has 64 divisors (see below), whose sum is σ = 93600000. Its totient is φ = 7487424.

The previous prime is 28078907. The next prime is 28078937. The reversal of 28078920 is 2987082.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11920 + ... + 14079.

It is an arithmetic number, because the mean of its divisors is an integer number (1462500).

Almost surely, 2^28078920 is an apocalyptic number.

28078920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28078920 is an abundant number, since it is smaller than the sum of its proper divisors (65521080).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28078920 is a wasteful number, since it uses less digits than its factorization.

28078920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26019 (or 26009 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 28078920 is about 5298.9546138838. The cubic root of 28078920 is about 303.9439243292.

The spelling of 28078920 in words is "twenty-eight million, seventy-eight thousand, nine hundred twenty".