Search a number
-
+
28557580 = 2251427879
BaseRepresentation
bin110110011110…
…0000100001100
31222201212122011
41230330010030
524302320310
62500031004
7464510152
oct154740414
958655564
1028557580
1115135807
129692464
135bbb59c
143b153d2
15279178a
hex1b3c10c

28557580 has 12 divisors (see below), whose sum is σ = 59970960. Its totient is φ = 11423024.

The previous prime is 28557553. The next prime is 28557643. The reversal of 28557580 is 8575582.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 713920 + ... + 713959.

It is an arithmetic number, because the mean of its divisors is an integer number (4997580).

Almost surely, 228557580 is an apocalyptic number.

28557580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28557580 is an abundant number, since it is smaller than the sum of its proper divisors (31413380).

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

28557580 is a wasteful number, since it uses less digits than its factorization.

28557580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1427888 (or 1427886 counting only the distinct ones).

The product of its (nonzero) digits is 112000, while the sum is 40.

The square root of 28557580 is about 5343.9292659989. The cubic root of 28557580 is about 305.6613080903.

The spelling of 28557580 in words is "twenty-eight million, five hundred fifty-seven thousand, five hundred eighty".

Divisors: 1 2 4 5 10 20 1427879 2855758 5711516 7139395 14278790 28557580