28170780 has 48 divisors (see below), whose sum is σ = 86050944. Its totient is φ = 6829120.

The previous prime is 28170767. The next prime is 28170797. The reversal of 28170780 is 8707182.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

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, 20682 + ... + 22001.

It is an arithmetic number, because the mean of its divisors is an integer number (1792728).

Almost surely, 2^28170780 is an apocalyptic number.

28170780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28170780 is an abundant number, since it is smaller than the sum of its proper divisors (57880164).

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

28170780 is a wasteful number, since it uses less digits than its factorization.

28170780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42706 (or 42704 counting only the distinct ones).

The product of its (nonzero) digits is 6272, while the sum is 33.

The square root of 28170780 is about 5307.6152837221. The cubic root of 28170780 is about 304.2750137145.

The spelling of 28170780 in words is "twenty-eight million, one hundred seventy thousand, seven hundred eighty".