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28765408 = 257281457
BaseRepresentation
bin110110110111…
…0110011100000
32000010102201111
41231232303200
524330443113
62504313104
7466334110
oct155566340
960112644
1028765408
1115267971
129772794
135c62069
143b6b040
1527d313d
hex1b6ece0

28765408 has 48 divisors (see below), whose sum is σ = 65094624. Its totient is φ = 12257280.

The previous prime is 28765403. The next prime is 28765417. The reversal of 28765408 is 80456782.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28765403) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62716 + ... + 63172.

It is an arithmetic number, because the mean of its divisors is an integer number (1356138).

Almost surely, 228765408 is an apocalyptic number.

28765408 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28765408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32547312).

28765408 is an abundant number, since it is smaller than the sum of its proper divisors (36329216).

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

28765408 is a wasteful number, since it uses less digits than its factorization.

28765408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 755 (or 747 counting only the distinct ones).

The product of its (nonzero) digits is 107520, while the sum is 40.

The square root of 28765408 is about 5363.3392583352. The cubic root of 28765408 is about 306.4010007534.

The spelling of 28765408 in words is "twenty-eight million, seven hundred sixty-five thousand, four hundred eight".

Divisors: 1 2 4 7 8 14 16 28 32 56 112 224 281 457 562 914 1124 1828 1967 2248 3199 3656 3934 4496 6398 7312 7868 8992 12796 14624 15736 25592 31472 51184 62944 102368 128417 256834 513668 898919 1027336 1797838 2054672 3595676 4109344 7191352 14382704 28765408