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28970780 = 2257319843
BaseRepresentation
bin110111010000…
…0111100011100
32000111212102212
41232200330130
524404031110
62512535552
7501150626
oct156407434
960455385
1028970780
11153981a3
1298515b8
136004697
143bc1c16
152823e05
hex1ba0f1c

28970780 has 24 divisors (see below), whose sum is σ = 61675152. Its totient is φ = 11428992.

The previous prime is 28970779. The next prime is 28970789. The reversal of 28970780 is 8707982.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28970789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8462 + ... + 11381.

It is an arithmetic number, because the mean of its divisors is an integer number (2569798).

Almost surely, 228970780 is an apocalyptic number.

28970780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28970780 is an abundant number, since it is smaller than the sum of its proper divisors (32704372).

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

28970780 is a wasteful number, since it uses less digits than its factorization.

28970780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19925 (or 19923 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 41.

The square root of 28970780 is about 5382.4511145016. The cubic root of 28970780 is about 307.1284604239.

The spelling of 28970780 in words is "twenty-eight million, nine hundred seventy thousand, seven hundred eighty".

Divisors: 1 2 4 5 10 20 73 146 292 365 730 1460 19843 39686 79372 99215 198430 396860 1448539 2897078 5794156 7242695 14485390 28970780