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18871868 = 2223205129
BaseRepresentation
bin100011111111…
…1011000111100
31022111210100002
41013333120330
514312344433
61512253432
7316260011
oct107773074
938453302
1018871868
11a71a794
1263a1278
133ba9ab2
142713708
1519cb9e8
hex11ff63c

18871868 has 12 divisors (see below), whose sum is σ = 34461840. Its totient is φ = 9025632.

The previous prime is 18871861. The next prime is 18871873. The reversal of 18871868 is 86817881.

It is a super-2 number, since 2×188718682 = 712294803618848, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18871861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102473 + ... + 102656.

It is an arithmetic number, because the mean of its divisors is an integer number (2871820).

Almost surely, 218871868 is an apocalyptic number.

It is an amenable number.

18871868 is a deficient number, since it is larger than the sum of its proper divisors (15589972).

18871868 is a wasteful number, since it uses less digits than its factorization.

18871868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205156 (or 205154 counting only the distinct ones).

The product of its digits is 172032, while the sum is 47.

The square root of 18871868 is about 4344.1763315961. The cubic root of 18871868 is about 266.2389734389.

The spelling of 18871868 in words is "eighteen million, eight hundred seventy-one thousand, eight hundred sixty-eight".

Divisors: 1 2 4 23 46 92 205129 410258 820516 4717967 9435934 18871868