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28905408 = 2632767107
BaseRepresentation
bin110111001000…
…0111111000000
32000101112202200
41232100333000
524344433113
62511313200
7500456220
oct156207700
960345680
1028905408
1115353074
12981b800
135cb09bc
143ba6080
15280e873
hex1b90fc0

28905408 has 168 divisors, whose sum is σ = 96999552. Its totient is φ = 8059392.

The previous prime is 28905407. The next prime is 28905413. The reversal of 28905408 is 80450982.

28905408 is a `hidden beast` number, since 28 + 90 + 540 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (168).

It is a super-2 number, since 2×289054082 = 1671045223292928, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28905407) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 270091 + ... + 270197.

Almost surely, 228905408 is an apocalyptic number.

28905408 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 28905408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48499776).

28905408 is an abundant number, since it is smaller than the sum of its proper divisors (68094144).

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

28905408 is a wasteful number, since it uses less digits than its factorization.

28905408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199 (or 186 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 28905408 is about 5376.3749869220. The cubic root of 28905408 is about 306.8972766559.

The spelling of 28905408 in words is "twenty-eight million, nine hundred five thousand, four hundred eight".